Method for oxidation for preparing alkenes and carboxylic acids

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to the improved method for oxidation of (C2-C4)-alkane and preparing the corresponding alkene and carboxylic acid. Method involves addition of this alkane to contact with molecular oxygen-containing gas in oxidative reaction zone and optionally at least one corresponding alkene and water in the presence of at least two catalysts with different selectivity. Each catalyst is effective in oxidation of alkane to corresponding alkene and carboxylic acid resulting to formation of product comprising alkene, carboxylic acid and water wherein the molar ratio between alkene and carboxylic acid synthesized in the reaction zone is regulated or maintained at the required level by regulation the relative amounts of at least two catalyst in the oxidative reaction zone. Also, invention relates to the combined method for preparing alkyl carboxylate comprising abovementioned stage in preparing alkene and carboxylic acid in the first reaction zone. Then method involves the stage for addition of at least part of each alkene and carboxylic acid prepared in the first reaction zone to the inter-contacting in the second reaction zone the presence of at least one catalyst that is effective in preparing alkyl carboxylate to yield this alkyl carboxylate. Also, invention relates to a method for preparing alkenyl carboxylate comprising the abovementioned stage for preparing alkene and carboxylic acid in the first reaction zone and stage for inter-contacting in the second reaction zone of at least part of each alkene and carboxylic acid synthesized in the first reaction zone and molecular oxygen-containing gas in the presence of at least one catalyst that is effective in preparing alkenyl carboxylate and resulting to preparing this alkenyl carboxylate.

EFFECT: improved method for oxidation.

30 cl, 1 dwg, 5 tbl, 14 ex

 

The present invention relates to a method of oxidation With2-C4alkane to the corresponding alkene and carboxylic acid, and to the United ways in which the alkene and carboxylic acid is further used as reagents.

Carboxylic acids can be used as the source materials upon receipt of alkenylbenzenes. So, for example, acetic acid is used upon receipt of vinyl acetate, which in the industry is produced by introduction of ethylene and acetic acid into contact with molecular oxygen in the presence of a catalyst, effective upon receipt of vinyl acetate. Acceptable catalyst may include palladium acetate of an alkali metal as a promoter and an optional copromotor (for example, gold or cadmium), deposited on a catalyst carrier. Acetic acid may be obtained by catalytic oxidation of ethylene and/or ethane.

United ways of obtaining acetic acid and/or vinyl acetate in the art known. In EP-A 0877727 described the United way of getting acetic acid and/or vinyl acetate in any given ratio and variable proportions of the gaseous feedstock comprising ethylene and/or ethane. This combined method comprises a first stage in which ethylene and/or ethane in the first Rea the operating area of the catalytically oxidized to obtain a first product, including acetic acid, water, ethylene, and optionally ethane, carbon monoxide, carbon dioxide and/or nitrogen. Next, acetic acid and ethylene obtained in this first reaction zone, the second reaction zone is introduced into contact with the containing molecular oxygen gas in the presence of a catalyst to obtain a second product comprising vinyl acetate, water, acetic acid and optionally ethylene. The mention of any regulation of the ratio between the obtained ethylene and acetic acid in the catalytic oxidation of ethane and/or ethylene is missing.

Research 2244, published in June 1992, No. 338, described by way of the oxidation of ethane and/or ethylene with obtaining acetic acid, in the exercise of which is obtained as a by-product carbon monoxide is oxidized to carbon dioxide. In accordance with this document acetic acid, unreacted ethane (if it contains) and ethylene with carbon dioxide or without him and removed water is directed into the reactor containing suitable to obtain ethyl acetate catalyst, or with the addition of oxygen to produce vinyl acetate. In this document, the mention of the regulation of the ratio between obtained at the stage of oxidation of ethylene and acetic acid is also missing.

Upon receipt blame the acetate from ethylene and acetic acid, the target value of the molar ratio between ethylene and acetic acid in fresh raw material is one or close to one. Therefore, during the joint process, in which ethane oxidized in the oxidation reaction zone with the receipt of ethylene and acetic acid, for use in the second reaction zone upon receipt of vinyl acetate order to maximize the effectiveness of this combined process, as well as the output of the vinyl acetate to the desired value of the molar ratio between ethylene and acetic acid produced in the oxidation reaction zone, is one or close to one that depends on the selectivity/yield in the second reaction zone.

Thus, there is still a need in the oxidation method With2-C4alkane to the corresponding alkene and carboxylic acid, which regulate or support at a given level, the molar ratio between the received alkene and carboxylic acid.

Therefore, the present invention proposes a method of oxidation With2-C4alkane to the corresponding alkene and carboxylic acid, which includes the introduction of this alkane oxidation reaction zone in contact with the containing molecular oxygen gas, and optionally at least one corresponding alkene and water in the presence of at least two catalysts with different selectively, each of which effect the Yong in the oxidation of alkane to the corresponding alkene and carboxylic acid, with the receipt of the product, including alkene, carbolic acid and water, and in which the molar ratio between produced in this oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level by controlling in such oxidation reaction zone relative amounts of at least two catalysts.

Each of the components alkane containing molecular oxygen gas, alkene and water, you can enter into the oxidation reaction zone in the form of fresh feedstock and/or recycle component.

The selectivity of the catalyst in relation to the alkene or carboxylic acid is defined as the proportion of reagent that using such a catalyst is converted to alkene or carboxylic acid.

If during operation in the oxidation reaction zone is deactivated one or more catalysts and during the process is necessary to replace the catalyst, the molar ratio between the received alkene and carboxylic acid can be maintained at a constant predetermined level of regulation in the oxidation reaction zone relative amounts of catalysts. For example, if during the process in the oxidation reaction zone is independent changes in the activity and/or selectivity of the catalysts, such regulation may include Semenov oxidation reaction zone at least part of the catalyst by introducing this oxidation reaction zone catalyst in proportions different from the proportions of catalysts in which they are already in the oxidation reaction zone, in order to maintain the molar ratio between the received alkene and carboxylic acid. Conversely, if the catalyst in the reactor are deactivated so that their individual selectivity does not change, maintaining the molar ratio between the received alkene and carboxylic acid by replacement of catalysts in the oxidation reaction zone in the same relative amounts in which they are in this oxidation reaction zone is located.

The present invention also offers a method of regulating the molar ratio between the received alkene and carboxylic acid, for example, in response to changes in the needs or requirements of the subsequent process line processes by regulating the relative quantities of at least two catalysts in the oxidation reaction zone.

The method according to the present invention is particularly effective when the resulting alkene and/or carboxylic acid at least partially used in subsequent in the United technological line processes, such as (a) upon receipt of ester by the reaction of carboxylic acid with an alkene or alcohol, or (b) upon receipt of alkenylboronic reaction containing mol the molecular oxygen gas with a carboxylic acid and alkene. From the product withdrawn from the oxidation reaction zone, alkene and/or carboxylic acid can be selected, and subsequently in a production line processes can be used for more number of alkene and/or carboxylic acid.

In yet another embodiment, the present invention alkene and carboxylic acid can be obtained in a molar ratio that is acceptable for use in subsequent United in a production line process, for example (a) upon receipt of ester by the reaction of carboxylic acid with an alkene or (b) upon receipt of alkenylboronic reaction containing molecular oxygen gas with a carboxylic acid and alkene. If the alkene and/or carboxylic acid from the reaction product by itself, is not isolated and separately do not add up process line process, the appropriate molar ratio obtained in the oxidation reaction zone with alkene and carboxylic acid is approximately 1:1, for example from 0.8:1 to 1.4:1. If the alkene and/or carboxylic acid from the reaction product of the oxidation allocate individually or separately added to the subsequent process line process can be achieved in a different ratio. When this molar ratio of alkene and carboxylic acid can be adjusted by nab, the emer, in order to meet the changing requirements of the market or depending on the availability of raw materials, through regulation in the oxidation reaction zone relative amounts of at least two catalysts. Suitable molar ratio obtained in the oxidation reaction zone with alkene and carboxylic acid is in the range from 1:10 to 10:1.

Thus, the present invention offers a unified way of obtaining alkylcarboxylic, which includes the following stages:

(a) introduction into the oxidation reaction zone With2-C4alkane in contact with the containing molecular oxygen gas, and optionally at least one corresponding alkene and water in the presence of at least two catalysts with different selectivity, each of which is effective in the oxidation of the alkane to the corresponding alkene and carboxylic acid, to obtain a product comprising alkene, carboxylic acid and water; and

(b) introducing a second reaction zone at least part of each of the resulting first reaction zone alkene and carboxylic acid in mutual contact in the presence of at least one catalyst effective upon receipt of alkylcarboxylic, obtaining this alkylcarboxylic,

moreover, in this method, the molar ratio between what we receive in this oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level by controlling in such oxidation reaction zone relative quantities on at least two catalysts.

In addition, according to another variant implementation of the present invention offers a unified way of obtaining alkenylacyl, which includes the following stages: (a) introduction into the oxidation reaction zone With2-C4alkane in contact with the containing molecular oxygen gas, and optionally at least one corresponding alkene and water in the presence of at least two catalysts with different selectivity, each of which is effective in the oxidation of the alkane to the corresponding alkene and carboxylic acid, to obtain a product comprising alkene, carboxylic acid and water; and (b) introducing a second reaction zone at least part of each of the resulting first reaction zone alkene and carboxylic acid containing molecular oxygen gas in mutual contact in the presence of at least one catalyst effective upon receipt of alkenylacyl, obtaining this alkenylacyl, and in this method, the molar ratio between produced in this oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level by controlling in such oxidation reaction zone relative amounts of at least two catalysts.

In prefer enom embodiment, the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid for use in the second reaction zone for receiving alkylcarboxylic or alkenylboronic support at the level of approximately 1:1, for example from 0.8:1 to 1.4:1.

Preferred implementation of the present invention With2-C4alkanol is ethane, and the corresponding alkene is an ethylene, and the corresponding carboxylic acid is acetic acid. These products can be introduced into the reaction in the subsequent process line producing ethyl acetate or containing molecular oxygen gas with the receipt of vinyl acetate.

The oxidation reaction is typically conducted in a heterogeneous environment using solid catalysts and reagents in the liquid phase.

Catalysts effective for the oxidation of the alkane to alkene and carboxylic acid may include any acceptable catalysts known in the art, such as those used for the oxidation of ethane to ethylene and acetic acid, are presented in US 4596787, EP-A 0407091, DE 19620542, WO 99/20592, DE 19630832, WO 98/47850, WO 99/51339, EP-A 1043064, WO 99/13980, US 5300682 and US 5300684, the contents of which are incorporated into this description by reference.

US 4596787 relates to a method of low temperature oxidoreductases of ethane to ethylene using a catalyst, corresponding to the empirical formula MoaVbNbcSbdXeas shown below, and these elements are combined with oxygen.

EP-A 0407091 from OSISA to a method and catalyst for producing ethylene and/or acetic acid by the oxidation of ethane and/or ethylene in the presence of the oxidation catalyst, including molybdenum, rhenium and tungsten.

DE 19620542 relates to oxidation catalysts based on molybdenum, palladium and rhenium for obtaining acetic acid from ethane and/or ethylene.

WO 99/20592 relates to a method for selective receipt of acetic acid from ethane, ethylene or mixtures thereof and oxygen at high temperature in the presence of a catalyst corresponding to the formula MoandPdbbXcYdin which X represents one or more of the following elements: Cr, Mn, Nb, TA, Ti, V, Te and W; Y represents one or more of the following elements B, Al, Ga, In, Pt, Zn, Cd, Bi, Ce, Co, Rh, Ir, Cu, Ag, Au, Fe, Ru, Os, K, Rb, Cs, Mg, Ca, Sr, Ba, Nb, Zr, Hf, Ni, P, Pb, Sb, Si, Sn, Tl, and U, and represents 1, b represents a number from 0.0001 to 0.01, with denotes a number from 0.4 to 1, and d denotes a number from 0,005 to 1.

DE-A1 19630832 belongs to the similar catalytic composition, and which denotes 1, b>0, C>0, d denotes a number from 0 to 2. In the preferred embodiment, and represents 1, b represents a number from 0.0001 to 0.5, with denotes a number from 0.1 to 1.0, and d denotes a number from 0 to 1.0.

WO 98/47850 relates to a method for producing acetic acid from ethane, ethylene or mixtures thereof in the presence of a catalyst corresponding to the formula WaXbYcZdin which X represents one or more of the following elements: Pd, Pt, Ag and Au, Y represents one or more of the following elements: V, Nb, Cr, Mn, Fe, Sn, Sb, Cu, Zn, U, Ni and Bi, a-Z about the mean one or more of the following elements: Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Sc, Y, La, Ti, Zr, Hf, Ru, Os, Co, Rh, Ir, B, Al, Ga, In, Tl, Si, Ge, Pb, P, As, and Te, and 1 denotes that b>0, C>0, d denotes a number from 0 to 2.

WO 99/51339 relates to catalytic compositions for the selective oxidation of ethane and/or ethylene to acetic acid; the composition comprises in combination with oxygen the elements MoaWbAgcIrdXeYfwhere X denotes the elements Nb and V; Y represents one or more elements selected from the group including Cr, Mn, TA, Ti, In, Al, Ga, In, Pt, Zn, Cd, Bi, CE, Co, Rh, Cu, Au, Fe, Ru, Os, K, Rb, Cs, Mg, Ca, Sr, Ba, Zr, Hf, Ni, P, Pb, Sb, Si, Sn, Tl, U, Re and Pd; and a , b, C, d, e, and f denotes the gram-atom ratios of the elements, in which 0<and≤1; 0≤b<1 and a+b=1;0<(C+d)≤0,1; 0<e≤2 u 0≤f≤2.

EP-A 1043064 relates to catalytic compositions for the oxidation of ethane to ethylene and/or acetic acid and/or for the oxidation of ethylene to acetic acid; the composition comprises in combination with oxygen the elements molybdenum, vanadium, niobium and gold in the absence of palladium according to the empirical formula: MoaWbAucVdNbeYfin which Y represents one or more elements selected from the group including Cr, Mn, TA, Ti, In, Al, Ga, In, Pt, Zn, Cd, Bi, CE, Co, Rh, Ir, Cu, Ag, Fe, Ru, Os, K, Rb, Cs, Mg, Ca, Sr, Ba, Zr, Hf, Ni, P, Pb, Sb, Si, Sn, Tl, U, Re, Te, La and Pd; and a , b, C, d, e, and f denotes the gram-atom ratios of the elements, in which 0<andࣘ 1; 0≤b<1 and a+b=1; 10-5<with≤0,02; 0<d≤2; 0<e≤1 and 0≤f≤2.

WO 99/13980 relates to a catalyst for selective oxidation of ethane to acetic acid corresponding to the formula MoaVbNbcXdin which X denotes at least one promoter element selected from the group comprising P, b, Hf, Te and As; and denotes a number in the range from about 1 to about 5; b is 1; C represents a number in the range from about 0.01 to about 0.5; and d denotes a number in the range from greater than 0 to about 0.1.

US 5300682 relates to the application of oxidation catalyst with the empirical formula VPaMbOx,where M denotes one or more elements of a number of Co, Cu, Re, Fe, Ni, Nb, Cr, W, U, TA, Ti, Zr, Hf, Mn, Pt, Pd, Sn, Sb, Bi, Ce, As, Ag and Au, and denotes a number from 0.5 to 3, b is 0,1, and x corresponds to the valence requirements.

US 5300684 refers to the oxidation reaction in the fluidized bed using, for example, Mo0,37REof 0.25V0,26NB0,07SB0,03CA0,02OX

Other acceptable for use in the present invention, the oxidation catalysts presented in the application WO 99/13980, which refers to the use of catalysts with elements in combination with oxygen in the relative gram-atom ratios of MoaVbNbcXdwhere X denotes P, b, Hf, Te, or s; US 6030920, which refers to the use of catalysts with elements in combination with oxygen in the relative gram-atom ratios of MoaVbNbcPddthe application WO 00/00284, which refers to the use of catalysts with elements in combination with oxygen in the relative gram-atom ratios of MoaVbNbcPddand/or MoaVbLacPdd;US 6087297, which refers to the use of catalysts with elements in combination with oxygen in the relative gram-atom ratios of MoaVbPdcLad; application WO 00/09260, which refers to the use of catalysts with elements in combination with oxygen in the relative gram-atom ratios of MoaVbLacPddNbeXf,where X denotes a Cu or Cr, and e and f may denote zero; applications WO 00/29106 and WO 00/29105 that relate to the use of catalysts with elements in combination with oxygen in the relative gram-atom ratios of MoaVbGacPddNbeXfwhere X denotes the La, Te, Ge, Zn, Si, In or W, and the application WO 00/38833, which refers to the use of catalysts with elements in combination with oxygen in the relative gram-atom ratios of MoaVb LacPddNbeXfwhere X represents Al, Ga, Ge or Si, the content of which is incorporated into this description by reference.

Solid catalysts are effective in the oxidation of C2-C4alkane can be carriers and not printed on the media. Examples of acceptable carriers include silica, diatomaceous earth, montmorillonite, aluminum oxide, silicon dioxide/aluminum oxide, zirconium dioxide, titanium dioxide, silicon carbide, activated carbon and mixtures thereof.

Solid catalysts are effective in the oxidation of C2-C4alkane may be used in the form of a fixed or fluidized bed.

Assume, apparently, that the oxidation catalyst will provide the oxidation of at least part of any alkene sent to the oxidation reaction zone, for example, to the corresponding carboxylic acid.

The molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid can be adjusted or maintained at a given level, just before starting the reaction with a single catalyst, followed by the replacement of at least part of the catalyst of at least one of the other catalysts with different selectivity for alkene and carboxylic acid.

The molar ratio of alkene and CT is about acid can be adjusted or maintained by the replacement of at least part of the catalyst in the oxidation reaction zone at least one or more catalysts with selectivity, non-selectivity of the catalyst or catalysts already in the oxidation reaction zone. So, for example, catalysts that are initially in the oxidation reaction zone may be in total more selective to obtain alkene; next, the molar ratio between obtained in the oxidation reaction zone with alkene and acetic acid can be adjusted by replacing at least part of the catalyst already present in the oxidation reaction zone, the catalyst or catalysts with improved selectivity for carboxylic acids.

The catalyst or catalysts effective for the oxidation of the alkane to alkene and carboxylic acid, can be replaced by methods in the art known. For example, during the process in the fluidized bed, the catalyst can be removed by either ablation or intentionally using known tools and replace using known means.

Containing molecular oxygen gas used in the oxidation reaction zone, may be air or a gas richer or poorer in molecular oxygen than air. Acceptable gas can represent, for example, oxygen diluted with an appropriate diluent, such as nitrogen or carbon dioxide. Before actually containing molecular oxygen gas is oxygen. In a preferred embodiment, at least some part containing molecular oxygen gas is directed to the oxidation reaction zone, regardless of the filing alkangovolo and optional alkinoos raw materials and recycle all materials.

Alkane and, if used, alkene, directed to the oxidation reaction zone in the method according to the present invention can be practically pure or can be mixed, for example, with one or more materials such as nitrogen, methane, carbon dioxide, carbon monoxide, hydrogen and a small amount3/S4alkenes/alkanes.

It is advisable to take an optional alkene (in the form of fresh raw materials and recycle component) is from 0 to 50 mol.% inclusive of all materials sent to the oxidation reaction zone, including recycle materials, preferably from 1 to 20 mol.%, more preferably from 1 to 15 mol.%.

It is advisable to take an optional water (in the form of fresh raw materials and recycle component) is from 0 to 50 mol.% inclusive of all materials sent to the oxidation reaction zone, including recycle materials, preferably from 0 to 25 mol.%.

When in the oxidation reaction zone use solid catalysts, alkane, optional alkene containing molecular to slort gas and recycle all gases in the preferred embodiment, is passed through the oxidation reaction zone with length of stay in it, the corresponding total average hourly rate of gas supply (SPG) from 500 to 10000 h-1and SSPG defined as the amount of [calculated at standard temperature and pressure (CTD)] of the gas passing through the reactor, divided by the bulk volume of the precipitated catalyst.

The oxidation reaction of the present invention can be effectively carried out at a temperature in the range from 100 to 400°typically in the range from 140 to 350°C.

The oxidation reaction of the present invention can be effectively carried out under atmospheric or elevated pressure, for example under a gauge pressure in the range of 80 to 400 psi.

During the oxidation reaction of the present invention typically can be achieved in the conversion of alkane in the interval from 1 to 99%.

During the oxidation reaction of the present invention typically can be achieved in the conversion of oxygen in the range from 30 to 100%.

Acceptable performance of the catalyst during the oxidation reaction of the present invention is in the range from 10 to 10,000 g of carboxylic acid, such as acetic acid, per hour per kilogram of catalyst.

Depending on the nature of any catalyst used during any subsequent process line process, in particular when his PR is the application for obtaining of alkenylacyl, such as vinyl acetate, it is necessary that the content of carbon monoxide as a by-product in the first gaseous product was low, as it can have a negative impact on some of the catalysts for alkenylacyl, in particular vinyl acetate. Thus, in a preferred embodiment, in the oxidation reaction zone using a catalyst, which causes the formation of small amounts of carbon monoxide as a by-product. For oxidation of carbon monoxide to carbon dioxide in the oxidation reaction zone may be used for additional catalytic component. It can be present in the catalyst or oxidation catalysts or in the secondary reaction zone.

When the oxidation process as a reagent use ethane, the product comprises acetic acid, ethylene and water and may contain ethane and oxygen, inert gaseous components, such as argon and nitrogen, as well as by-products, acetic aldehyde, carbon monoxide and carbon dioxide. Acetaldehyde and carbon monoxide may be turning containing molecular oxygen gas with the formation of, respectively, acetic acid and carbon dioxide or in a subsequent process line processes, or after return to PR the process in the oxidation reaction zone. The ethylene contained in the product of the oxidation reaction as unreacted reagent, if ethylene is included with the source material, and/or as a product of oxidation of ethane reactant.

The product of the oxidation process can be sent directly or indirectly, after one or more stages of separation, the second reaction zone together with optional additional number containing molecular oxygen gas, an optional additional amount of alkene and an optional additional amount of carboxylic acid to obtain alkenylacyl, such as vinyl acetate. Carboxylic acid and/or alkene can (but not necessarily) from the product of the oxidation process to allocate.

Unreacted alkane and/or alkene can be returned together or after at least partial separation from the subsequent process line process in the oxidation reaction zone directly or indirectly, after one or more stages of separation.

In the method according to the present invention can be applied is known in the art catalysts receiving alkenylbenzenes. So, for example, catalysts, effective upon receipt of vinyl acetate, which upon implementation of the present invention can be used in the second reaction zone, mo the ut enable, in particular, the catalysts are presented in GB 1559540, US 5185308 and EP-A 0672453, the contents of which are incorporated into this description by reference.

In GB 1559540 described catalyst, effective upon receipt of vinyl acetate by reaction of ethylene, acetic acid and oxygen, and the catalyst essentially consists of: (1) the catalyst carrier particle diameter is from 3 to 7 mm, and the specific pore volume is equal to from 0.2 to 1.5 ml/g, and the pH value of the suspension of this catalyst carrier in water concentration of 10 wt.% is from 3.0 to 9.0, (2) alloy of palladium-gold, distributed in the surface layer of the catalyst carrier, and this surface layer is at a distance of less than 0.5 mm above the surface of the carrier, palladium in the alloy is contained in an amount of from 1.5 to 5.0 g/l of catalyst, and the gold is contained in an amount of from 0.5 to 2.25 g/l of catalyst, and (3) from 5 to 60 g of the alkali metal acetate per liter of catalyst.

In the US 5185308 described catalyst impregnated with sheath, effective upon receipt of vinyl acetate from ethylene, acetic acid and oxygen-containing gas, and the catalyst essentially consists of: (1) the catalyst carrier particle diameter which is from about 3 to about 7 mm, and the specific pore volume is equal to from 0.2 to 1.5 ml/g, (2) palladium, and gold, distributed in the thick layer is 1.0 mm particles of the catalyst carrier, and (3) from about 3.5 to about 9.5 wt.% potassium acetate, where the value of the mass ratio between gold and palladium in the catalyst is in the range of from 0.6 to 1.25.

In EP-A 0672453 described palladium catalysts for the conduct of processes of production of vinyl acetate in the fluidized bed and cooking.

The advantage of using palladium catalyst is that all of the carbon monoxide produced in the first reaction zone, usually consumed in the presence of oxygen and palladium catalyst in the second reaction zone, thereby eliminating the need for a separate reactor for removing carbon monoxide.

The process of obtaining alkenylacyl, such as vinyl acetate, in the second reaction zone, as a rule, is carried out in heterogeneous conditions, and the reactants are in the gas phase.

In the second reaction zone to obtain alkenylboronic you can send additional number alkinoos reagent, as well as the alkene from the oxidation reaction zone as a product of the oxidation process and/or unspent alkinoos reagent.

Additional alkene introduced into the second reaction zone to obtain alkenylboronic may be almost pure or can be mixed, for example, with one or more such is the materials, as nitrogen, methane, carbon dioxide, carbon monoxide, hydrogen and a small amount3/S4alkenes/alkanes.

Containing molecular oxygen gas used in the second reaction zone to obtain alkenylacyl, may include a gas containing unreacted molecular oxygen, from the stage (a) and/or additional containing molecular oxygen gas.

Additional containing molecular oxygen gas, if used, may be air or a gas richer or poorer in molecular oxygen than air. Acceptable additional containing molecular oxygen gas may represent, for example, oxygen diluted with a suitable diluent, such as nitrogen or carbon dioxide. Preferred additional containing molecular oxygen gas is oxygen. In a preferred embodiment, at least some part containing molecular oxygen gas is directed to the second reaction zone, regardless of the submission as reagents alkene and carboxylic acid.

At least part of the carboxylic acid, which is directed to the second reaction zone may be liquid.

When the second reaction zone to obtain alkenylboronic use of solid catalysts, the product is discharged and the oxidation reaction zone, all additional alkene or carboxylic acid as reagents, recycle all materials containing molecular oxygen gas in the preferred embodiment, is passed through a second reaction zone at a compound average rate of gas supply (SPG) from 1000 to 10000 h-1.

The process of obtaining alkenylboronic in the second reaction zone can be effectively carried out at a temperature in the range from 140 to 200°C.

The process of obtaining alkenylboronic in the second reaction zone can be effectively carried out under a gauge pressure in the range of 50 to 300 psi.

The process of obtaining alkenylboronic in the second reaction zone can be effectively carried out as a process in a fixed or fluidized bed.

Upon receipt of alkenylboronic in the second reaction zone can be achieved, the degree of conversion of carboxylic acids in the range of from 5 to 80%.

Upon receipt of alkenylboronic in the second reaction zone can be achieved, the degree of conversion of the oxygen in the range from 20 to 100%.

Upon receipt of alkenylboronic in the second reaction zone can be achieved, the degree of conversion of the alkene in the range from 5 to 100%.

Acceptable performance of the catalyst upon receipt of alkenylboronic in the second reaction zone is in INTA the shaft 10 to 10000 g alkenylboronic/h/kg of catalyst.

When the method according to the present invention as alkane use ethane, the product withdrawn from the second reaction zone to obtain alkenylacyl, may include vinyl acetate, water and acetic acid, and optionally unreacted ethylene, ethane, acetaldehyde, nitrogen, argon, carbon monoxide and carbon dioxide. This product can be divided azeotropic distillation at the top fraction comprising vinyl acetate and water, and the bottom fraction comprising acetic acid and water. The bottom fraction could be taken from the distillation column in a liquid form from the base of the column or in the form of steam from one or several steps above the base of the column. Before this stage distillation from the second product can remove ethylene, ethane, acetaldehyde, carbon monoxide and carbon dioxide if they are reasonable in view of the upper gaseous fraction scrubbing column, from the base of which divert the liquid fraction comprising vinyl acetate, water and acetic acid. Ethylene and/or ethane can be returned to the step (a) and/or stage (b).

From the top fraction to allocate suitable vinyl acetate, for example, by decantation. If necessary, the selected vinyl acetate can be subjected to additional purification by a known method.

The bottom fraction comprising acetic acid and water, until after anitelea cleaning, preferably without treatment, you can return to the step (b) of the process. According to another variant of the bottom fraction produce acetic acid, which optionally can be subjected to additional purification by a known method, for example by distillation.

An acceptable method of obtaining esters by the reaction of carboxylic acid with an alkene is proposed in the application EP-A 0926126, the contents of which are incorporated into this description by reference and object which is a method of esterification, including the reaction of accession by the interaction of lower olefin with a saturated lower aliphatic monocarboxylic acid in the vapor phase in the presence of heteropolyanions catalyst, characterized in that the reaction of lead in several reactors, placed sequentially in such a way that gases including unreacted gases and the products originating from the first reactor as a gaseous raw material is sent to the second reactor, and the products originating from the second reactor as a gaseous raw material is sent to the third reactor, etc. in all subsequent reactors and gaseous raw materials for each of the subsequent reactors, starting with the second, as a reagent add an aliquot of monocarboxylic acid to gaseous raw materials for each of the subsequent reactors, starting with the second, to keep within the given interval, the ratio between the olefin and the monocarboxylic acid.

The invention is further illustrated by the example with reference to the drawing and the following examples.

In this drawing, in the form of a block diagram of the plant that is acceptable for use in the method according to the present invention. This installation includes the oxidation reaction zone (1), provided with a means (3) supply of ethane and optionally ethylene, a means (4) feed containing molecular oxygen gas, means (5) feed recycle gas comprising ethane and optionally ethylene, and outlet means (18) for the first product. Depending on the scale, the method of oxidation reaction zone (1) may include either a single reactor or multiple reactors, placed in parallel or sequentially.

The installation also includes a second reaction zone (2) for acetoxysilane of ethylene to vinyl acetate, which is provided with means (17) for transporting at least part of the product from the first reaction zone into the second reaction zone, means (9) feed containing molecular oxygen gas, means (10) feed recycle of acetic acid and an optional tool or means (8) feeding ethylene and/or acetic acid. Depending on the scale of the domestic is the way the second reaction zone (2) may include either a single reactor, or multiple reactors, placed in parallel or sequentially.

Next, the installation includes the optional scrubber (6) for the first reaction product, scrubber (12) for the product from the second reaction zone, means (13) for separating acetic acid from the product from the second reaction zone, means (14) for the purification of vinyl acetate, an optional means (15) for the purification of acetic acid and one or more separation means (16) for separation of carbon dioxide from the recycle gas withdrawn from the second reaction zone, and an optional allocation of ethylene in the product quality.

During operation the oxidation reaction zone (1) provide at least two catalysts, which have different selectivity, but each of which is effective for the oxidation of ethane with obtaining acetic acid and ethylene. As oxidation catalysts, it is advisable to use solid catalysts. Containing molecular oxygen gas is fed into the oxidation reaction zone (1) from (4) flow through one or more inlet holes. Gaseous source material, including ethane and optionally ethylene, send in the oxidation reaction zone (1) from (3) filing. In the oxidation reactor of the means (5) submission enter recycle gas comprising ethane and ethyl is. Containing molecular oxygen gas, ethane and recycle gas is fed into the oxidation reaction zone through one or more inlet holes separately or in partial or complete combination. At least one of the flows into the oxidation reactor, optionally includes water.

In the oxidation reactor to receive the first product that includes ethylene (as a product and/or unreacted starting material), acetic acid, water, optional unspent containing molecular oxygen gas and by-products such as carbon monoxide, carbon dioxide, inert components and acetic aldehyde. This product can (but not necessarily) be sent to the scrubber (16)from which the discharge gas and the liquid. After separation of by-products such as carbon dioxide, and optional allocation of ethylene in the product quality on the methods, which in the art is known, the gas can be returned to the process. Of the fluid can be selected, for example, by distillation of the acetic acid.

At least a portion of the first product by means of (17) is directed to the second reaction zone, which provides a catalyst acetoxysilane, suitable solid catalyst.

Containing molecular oxygen gas is fed to the second reaction zone of the means (9) poda is I. Acetic acid is directed to the second reaction zone of the tool (10) feed recycle material. In the second reaction zone of the vehicle or vehicles (8) filing is possible (but optional) to send an additional amount of ethylene and/or acetic acid. The first product containing molecular oxygen gas, recycle acetic acid, and optionally additional amounts of ethylene and/or acetic acid, serves in the second reaction zone through one or more inlet holes separately or in partial or complete combination.

In the second reaction zone ethylene, acetic acid and molecular oxygen to interact with the formation of the second product comprising vinyl acetate.

The second reaction product is fed into the scrubber (12), from which emit gas and liquid. In one or more stages (16) separation methods, which in the art is known from this gas into carbon dioxide and Recuperat optional ethylene as a product.

The remaining ethane and/or ethylene can be returned in the first and/or second reactor. Of the scrubbing liquid emit acetic acid and return to the second reaction zone. Acetic acid as a product, you may (optionally) be distinguished from recycle material by using (15), for example, by distillation. The vinyl acetate as PR the product is recovered from the scrubber liquid using (14), for example, by distillation.

If during operation in the oxidation reaction zone is deactivation of one or more catalysts and in the course of the process is necessary to replace the catalyst, the molar ratio between the obtained ethylene and acetic acid can be maintained at the specified level of control in the oxidation reaction zone relative amounts of catalysts. For example, if during the process in the oxidation reaction zone independently changing the activity and/or selectivity of the catalysts, the event in order to maintain the molar ratio between the obtained ethylene and acetic acid may include replacing in the oxidation reaction zone at least part of the catalyst introduction into the oxidation reaction zone catalyst in proportions that are different from the proportions of the catalysts in the oxidation reaction zone. In the opposite case, when the catalyst in the reactor are deactivated so that their individual selectivity does not change, it may be likely to maintain the molar ratio between the obtained ethylene and acetic acid by replacement of catalysts in the oxidation reaction zone with the catalyst in the same proportions as existed in the oxidation reaction zone.

In preferred options the ante molar ratio between ethylene and acetic acid, produced in the oxidation reaction zone for further use in the second reaction zone upon receipt of vinyl acetate support at a level of approximately 1:1, for example from 0.8:1 to 1.4:1. If the ethylene and/or acetic acid separated out from the reaction product of oxidation or separately injected into the second reaction zone upon receipt of vinyl acetate, it is possible to support a different value. Then the molar ratio between ethylene and acetic acid can be adjusted by variation in the oxidation reaction zone relative amounts of at least two catalysts, for example, in order to meet the changing requirements of the market or depending on the availability of raw materials.

Preparation of catalysts effective for the oxidation of ethane (catalyst A)

Dissolution 17,66 g of ammonium molybdate, of 2.92 g of ammonium Vanadate, 3,24 g of niobium chloride and 2.70 g of oxalic acid in 400 ml of water, heated to 70°With stirring prepared solution. To this solution was added to 24.6 mg of tetrachloroaurate ammonium and 15.5 mg of palladium acetate. After 15 min the solution was heated to the boiling temperature, followed by evaporation to dryness in a period of 2 hours the resulting "cake" of catalyst was crushed, and then caliciviral in static air atmosphere in a furnace at 400°C for 5 hours, the Catalyst has the been following nominal empirical formula:

Mo1,00Vof 0.25Nb0,12Au0,0007Pd0,008Ox

Preparation of catalysts B-D

The process of preparation of the catalyst And repeated, except that the gold-palladium component was replaced by a component selected from the group comprising gold, copper, silver and phosphorus, as shown in the following table I, with the receipt of a number of catalytic compositions based on base composition corresponding to the empirical formula Mo1,00Vof 0.25Nb0,125Oxbut with other promoters.

TABLE I
CatalystPreceding componentThe number preceding component in the form of salt (g)Nominal empirical formula of the catalyst
Catalyst BTetrachloroaurate ammonium0,428Mo1,00Vof 0.25Nb0,125Au0,014Ox
The catalyst InThe copper acetate0,280Mo1,00Vof 0.25Nb0,125Cu0,014Ox
Catalyst GAcetate silver0,111Mo1,00Vof 0.25Nb0,125Ag0,014Ox
Catalyst

D
Acid phosphate, ammo the Oia 0,090Mo1,00Vof 0.25Nb0,125P0,0025Ox

The method of carrying out the oxidation of ethane with catalysts a-D

Typically, 5 ml powdered catalyst from catalysts a-D were mixed with 15 ml of glass beads with a diameter beads of 0.4 mm, the receiving layer of the diluted catalyst with a volume of 20 ml of this diluted catalyst was loaded into the reactor with a porous layer made of alloy "Hastelloy", with an inner diameter of 12 mm and a length of 40 cm, the Catalyst was kept in the center of the reactor through a quartz pins together with inert supplementary material over a layer of catalyst. Next to check for leaks reactor was tested under a helium pressure of 20 bar. Then in helium under pressure 21 bar the catalyst was activated by heating to 220°With a speed of 5°C/min and aged for 4 h to ensure complete decomposition of the catalytic precursors.

Then the reactor was injected streams of ethane, 20% oxygen in helium and water, required to guarantee a desired inbound track. This composition consisted of 42% vol. ethane, 6,7% vol. oxygen, 25% vol. water, and the rest is helium. Total consumption of starting materials was maintained at this level, which is guaranteed SPG from 2000 to 9000/hours After establishment of equilibrium in ECENA 60 min from the waste stream was sampled gas for GC system (Unicam model 4400) for the quantitative determination of ethane, ethylene, oxygen and helium.

The desired temperature in the reactor was increased until then, until he got the degree of conversion of oxygen from 50 to 75%, as determined according to the calculation of the oxygen content in the exhaust stream. After another period of equilibrium within 60 min the catalyst was evaluated in a hospital during the period, as a rule, from 4 to 5 o'clock Volume of exhaust gas during the entire period of the experiment was measured by flow meter for water/gas. After a period of experiment liquid products were collected and weighed. The composition of gaseous and liquid products were determined by GC analysis [Unicam instruments models 4400 and 4200, respectively provided with a thermal conductivity detector (UCD) and a flame ionization detector (PID)].

According to the analysis of flow rates and composition of raw materials and products expected from the following options:

the degree of conversion of ethane=(number of moles of ethane, then the number of moles of ethane output)/number of moles of ethane at the entrance ×100;

the degree of conversion of oxygen = (number of moles of oxygen, then the number of moles of oxygen at the exit)/the number of moles of oxygen at the entrance ×100;

selectivity for acetic acid (mol.%) = (number of moles of acetic acid ×2 output)/(number of moles ×2 converted ethane)×100;

selectivity for Chilena (S, mol.%) = the number of moles of ethylene output - the number of moles of ethylene at the entrance)×2/(number of moles ×2 converted ethane)×100;

the selectivity for CO(mol.%) = (number of moles WITH output)/(number of moles ×2 converted ethane)×100;

the selectivity for CO2(Mol.%) = (number of moles of CO2output)/(number of moles ×2 converted ethane)×100;

the ratio of ethylene/Asón = (number of moles of ethylene output - the number of moles of ethylene at the entrance)/(number of moles of acetic acid)×100.

ODA (volumetric capacity), % = (g acetic acid)/kg catalytic layer/H.

Typically, the mass balance and carbon balance for the reaction was equal, as was established, 100±5%.

Examples 1-5

Catalysts a-D were used in the implementation of the above mentioned General method for the reaction. The results are presented in the following table II.

TABLE II

Oxidation reactions using catalytic base composition corresponding to the empirical formula Mo1,00Vof 0.25Nb0,125Oxand promoter components shown in table II.
CatalystCatalytic componentThe degree of conversion of ethane, %The selectivity for ethylene, % Selectivity for acetic acid, %Selectivity for carbon oxides, COx,%The molar ratio of ethylene/acetic acidODA by acetic acid, g/l cat./h
AndAu-Pd6,823,263,8a 12.70,36:1179
BAu10,034,654,98,80,63:1203
InCu8,035,855,68,3of 0.64:1158
GAg4,039,653,07,3to 0.75:1118
DP12,256,928,39,62,01:1130

The experimental results of the above examples show that the selectivity of different catalysts in relation to ethylene and acetic acid in the same reaction conditions are different. Thus, if in accordance with the method of the present invention in the oxidation reaction zone using at least two of the catalyst, the molar ratio between ethylene and acetic acid is the acid can be adjusted and maintained at a predetermined level by regulating the relative quantities of these at least two catalysts in the oxidation reaction zone.

Preparation of catalysts E-O is effective in the oxidation of ethane

Catalyst E

Dissolution 107,70 g of ammonium molybdate in 300 ml of distilled water heated to 70°With stirring prepared solution "And". Solution B was prepared by dissolving with stirring 30,41 g of ammonium Vanadate in 300 ml of distilled water heated to 70°C. the Solution "B" was prepared by dissolving with stirring 18,91 g of niobium chloride, 11,96 g of antimony acetate, 2.76 g of potassium carbonate and of 15.75 g of oxalic acid in 300 ml of distilled water heated to 70°C. Each of solutions a, B and C was allowed to stand for 15 min to allow the reaction components to maximize solubilisates. Then, the solution with stirring at 70°quickly added to solution B. the Solution B/was stirred for 15 min at 70°and then quickly added to the solution A. after 15 min the solution And/B/was heated to the boiling temperature, followed by evaporation to dryness in for 2.5 hours and Then the resulting "cake" of catalyst was transferred into a drying oven for further drying at 120°C for 2 hours After drying, the "pie" of the catalyst was ground to fine powder. Next, the resulting powder was sifted through a sieve with cell size of 0.2 mm, Then the sifted powdered catalyst was caliciviral in static air atmosphere in which ECI at 400° C for 4 h, the Catalyst was characterized by the following nominal empirical formula:

Mo1,000V0,426Nb0,115Sbof 0.066K0,033Ox

Catalyst W

The dissolution of 43.2 g of ammonium molybdate in 100 ml of distilled water heated to 70°With stirring prepared solution "And". Solution B was prepared by dissolving with stirring 11.4 g of ammonium Vanadate in 120 ml of distilled water heated to 70°C. the Solution "B" was prepared by dissolving with stirring 16,18 g ammoniumsulfate niobium and 2.5 g of oxalic acid in 100 ml of distilled water heated to 70°C. Each of solutions a, B and C was allowed to stand for 15 min to allow the reaction components to maximize solubilisates. Then, the solution with stirring at 70°quickly added to solution B. After mixing the solution B/W for 15 min at 70°it was quickly added to the solution A. after 15 min with stirring solution was added "G" (to 2.57 g of ammonium phosphate dissolved in 20 ml of water). Solution a/B/C/G was heated to the boiling temperature, followed by evaporation to dryness in for 1.5 hours Then dry "cake" of catalyst was transferred into a drying oven for further drying at 120°C for 16 hours After drying "pie" of the catalyst was ground to fine powder. Then received the initial powder was sifted through a sieve with cell size of 0.2 mm Then sifted powdered catalyst was caliciviral in static air atmosphere in a furnace at 350°C for 4 h, the Catalyst was characterized by the following nominal empirical formula:

Mo1,000V0,400Nb0,128P0,080K0,033Ox

Catalyst C

Dissolution 22,935 g of ammonium molybdate and 0,0357 g tetrachloroaurate of ammonia in 100 ml of distilled water heated to 70°With stirring prepared solution "And". Solution B was prepared by dissolving with stirring 6,434 g of ammonium Vanadate in 150 ml of distilled water heated to 70°C. the Solution "B" was prepared by dissolving with stirring 7,785 g ammoniumsulfate niobium in 100 ml of distilled water heated to 70°C. Each of solutions a, B and C was allowed to stand for 15 min to allow the reaction components to maximize solubilisates. Then, the solution with stirring at 70°quickly added to solution B. the Solution B/was stirred for 15 min at 70°and then quickly added to the solution A. after 15 min the solution And/B/was heated to the boiling temperature, followed by evaporation to dryness in for 1.5 hours Then dry "cake" of catalyst was transferred into a drying oven for further drying at 120°C for 2 hours After drying, the "pie" of the catalyst was crushed to encoders the CSOs powder. Next, the resulting powder was sifted through a sieve with cell size of 0.2 mm, Then the sifted powdered catalyst was caliciviral in static air atmosphere in a furnace at 400°C for 4 h, the Catalyst was characterized by the following nominal empirical formula:

Mo1,000V0,423Nb0,115Au0,008Ox

The catalyst And

Dissolution 20,97 g of ammonium molybdate and 0,0337 g of palladium acetate in 100 ml of distilled water heated to 70°With stirring prepared solution "And". Solution B was prepared by dissolving with stirring 7,749 g of ammonium Vanadate in 200 ml distilled water heated to 70°C. the Solution "B" was prepared by dissolving with stirring 5,626 g ammoniumsulfate niobium, 0,598 g of antimony acetate and 0,472 g of calcium nitrate in 200 ml of distilled water heated to 70°C. Each of solutions a, B and C was allowed to stand for 15 min to allow the reaction components to maximize solubilisates. Then, the solution with stirring at 70°quickly added to solution B. After mixing the solution B/W for 15 min at 70°it was quickly added to the solution A. after 15 min the solution And/B/was heated to the boiling temperature, followed by evaporation to dryness in for 1.5 hours Then dry "cake" of catalyst was transferred into a drying Cabinet to fill the preliminary drying at 120° C for 2 hours After drying, the "pie" of the catalyst was ground to fine powder. Next, the resulting powder was sifted through a sieve with cell size of 0.2 mm, Then the sifted powdered catalyst was caliciviral in static air atmosphere in a furnace at 350°C for 4 h, the Catalyst was characterized by the following nominal empirical formula:

Mo1,000V0,5577Nb0,0913Sb0,0168Ca0,0168Pd0,0013Ox

The catalyst To

Dissolution 15,491 g of ammonium molybdate in 100 ml of distilled water, heated to 80°With stirring prepared solution "And". Solution B was prepared by dissolving with stirring 5,594 g of ammonium Vanadate and 6.00 g of oxalic acid in 150 ml of distilled water, heated to 80°C. Each of solutions a and B were allowed to stand for 15 min to allow the reaction components to maximize solubilisates. Then, the solution with stirring at 80°quickly added to solution B. After mixing the solution A/B for 15 min at 80° (C) was added with stirring 0,0053 g of palladium acetate and 0.0004 g of lanthanum nitrate. After 15 min, this solution was heated to the boiling temperature, followed by evaporation to dryness in for 1.5 hours Then dry "cake" of catalyst was transferred into a drying oven for further drying at 120#x000B0; C for 2 hours After drying, the "pie" of the catalyst was ground to fine powder. Next, the resulting powder was sifted through a sieve with cell size of 0.2 mm, Then the sifted powdered catalyst was caliciviral in static air atmosphere in a furnace at 350°C for 4 h, the Catalyst was characterized by the following nominal empirical formula:

Mo1,000V0,584Pd0,000267La0,0001Ox

Catalysts L-O

Catalysts L-O was prepared by joint grinding of the catalyst 3 (based on Au) and (based on Pd), taken in different proportions. The relative amount of catalysts C and used for the preparation of catalysts L-O, are shown in table III.

TABLE III
CatalystCatalyst 3, wt.%The catalyst, wt.%
Catalyst L97,62,4
Catalyst Mfor 95.24,8
Catalyst N92,37,7
Catalyst O75.025,0

The method of carrying out the oxidation of ethane with catalysts E-About

Typically, 5 ml powdered catalyst from catalysts E-O was mixed with 15 m of the glass beads with a diameter beads of 0.4 mm, receiving layer of the diluted catalyst with a volume of 20 ml of this diluted catalyst was loaded into the reactor with a porous layer made of alloy "Hastelloy", with an inner diameter of 12 mm and a length of 40 cm, the Catalyst was kept in the center of the reactor through a quartz pins together with inert supplementary material over a layer of catalyst. Next to check for leaks reactor was tested under a helium pressure of 20 bar. Then in helium under a pressure of 16 bar, the catalyst was activated by heating to 220°With a speed of 5°C/min and aged for 1 h to ensure complete decomposition of the catalytic precursors.

Then the reactor was injected streams of ethane, 20% oxygen in helium and water, required to guarantee a desired inbound track. This composition consisted of 52% vol. ethane, 6,7% vol. oxygen, 10 vol.% ethylene, 5% vol. water, and the rest is helium. Total consumption of starting materials was maintained at this level, which is guaranteed SPG from 2000 to 9000/h, in particular 3200/h After establishing equilibrium within 60 min from the waste stream was sampled gas for GC system (Unicam model 4400) for the quantitative determination of ethane, ethylene, oxygen, and helium.

The desired temperature in the reactor was increased to 293°With the aim to achieve the same reactor temperature is from 299 to 301° For each of the catalysts from E to K, which helped to facilitate direct comparison. After another period of equilibrium within 60 min of liquid product has started to collect and continued during the period, usually 18 hours during this period the composition of the exhaust gas was determined by GC analysis (ProGC, Unicam). The amount of exhaust gas during the entire period of the experiment was measured by flow meter for water/gas. During the period of the experiment, the collected liquid products were isolated and weighed. The composition of the liquid products was determined by GC analysis (Unicam instruments models 4400 and 4200 equipped with the detectors respectively TKD and PID).

According to the analysis of flows of raw materials and products with the help of the equations given above in the description of the method of conducting the oxidation of ethane with catalysts a-D, expected consumption and the composition of materials, the degree of conversion of the starting materials, the selectivity with respect to the products, volumetric productivity (ODA) and the molar ratio between ethylene and acetic acid.

Examples 6 through 10.

When implementing the above-described General method of carrying out the reaction with catalysts from E to Of used catalysts from E to K. the Results are summarized in the following table IV.

TABLE IV
CatalystCatalytic componentThe degree of conversion of ethane, %The selectivity for ethylene, %Selectivity for acetic acid, %Selectivity for carbon oxides, COx, %The molar ratio of ethylene/acetic acidODA by acetic acid, g/kg cat./h
EMo-V-Nb-Sb-K4,512,959,327,80,22:197
WMo-V-Nb-P4,637,447,515.10,79:181
CMo-V-Nb-Au11,846,540,113,31.16:1175
AndMo-V-Nb-Sb-Ca-Pdthe 4.7NDand76,024,0-0,54:1b216
ToMo-V-Pd-La4,6NDand71,428,7-0,54:1b201
and the value of the selectivity to ethylene was impossible to calculate, because the catalyst was a net consumer of ethylene.

The negative value of the molar ratio between ethylene and acetic acid indicates, that the catalyst is not so much encouraged, so much was a net consumer of ethylene.

The data from the experiments of examples 6-10 indicate that the selectivity towards ethylene and acetic acid in the same reaction conditions with different catalysts were different, resulting in a molar ratio between ethylene and acetic acid could be adjusted and maintained at the specified level using the oxidation reaction zone of regulated quantities of two different catalysts.

Examples 11-14

When implementing the above-described General method of carrying out the reaction with catalysts from L to About the used catalysts from E to O. the Results are summarized in the table below V.

TABLE V
CatalystCatalytic componentThe degree of conversion of ethane, %The selectivity for ethylene, %Selectivity for acetic acid, %Selectivity for carbon oxides, COx, %The molar ratio of ethylene/acetic acidODA by acetic acid, g/kg cat./h
CMo-V-Nb-Au11,846,5 40,113,31,16:1175
L97,6 C - 2.48,536,547,516,0of 0.77:1149
M95,2 C - 4,87,08,266,425,40,12:1172
N92,3 C - 7,7 And6,2NDa73,726,3-0.08:!b179
About75,0 C - 25,05,0NDa75,824,2-0.41:!b203
AndMo-V-Nb-Sb-Ca-Pdthe 4.7NDa76,024,0-0,54:1b216
andandbhave the values listed in the above table IV.

The study of data of table V clearly shows that the regulation of the relative amounts of different catalysts C and in the oxidation reaction zone allows you to maintain the molar ratio between ethylene and acetic acid at the specified level.

1. The method of oxidation With2-C4alkane to the corresponding alkene and carboxylic acid, to the second includes the introduction of this alkane oxidation reaction zone in contact with the containing molecular oxygen gas, and optionally at least one corresponding alkene and water in the presence of at least two catalysts with different selectivity, each of which is effective in the oxidation of the alkane to the corresponding alkene and carboxylic acid, to obtain a product comprising alkene, carboxylic acid and water and in which the molar ratio between produced in this oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level by controlling in such oxidation reaction zone relative amounts of at least two catalysts.

2. The method according to claim 1, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid is in the range from 1:10 to 10:1.

3. The method according to claim 2, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid ranges from 0.8:1 to 1.4:1.

4. The method according to any of the preceding paragraphs, in which the alkane is a ethane, and the corresponding alkene is ethylene, and the corresponding carboxylic acid is acetic acid.

5. The method according to any of the preceding paragraphs, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level of replacing part of catalyst (catalysts), sotiriadis is in the oxidation reaction zone, at least one or more catalysts with selectivity that is different from the selectivity of the catalyst (catalysts)in the oxidation reaction zone.

6. The method according to any of the preceding paragraphs, in which at least one of the at least two catalysts in the oxidation reaction zone comprises molybdenum.

7. The method according to claim 6, in which each catalyst in the oxidation reaction zone comprises molybdenum.

8. United way of obtaining alkylcarboxylic, which includes the following stages:

(a) introduction into the oxidation reaction zone With2-C4alkane in contact with the containing molecular oxygen gas, and optionally at least one corresponding alkene and water in the presence of at least two catalysts with different selectivity, each of which is effective in the oxidation of the alkane to the corresponding alkene and carboxylic acid, to obtain a product comprising alkene, carboxylic acid and water; and

(b) introducing a second reaction zone at least part of each of the resulting first reaction zone alkene and carboxylic acid in mutual contact in the presence of at least one catalyst effective upon receipt of alkylcarboxylic, obtaining this alkylcarboxylic,

pricing this method, the molar ratio between produced in this oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level by controlling in such oxidation reaction zone relative amounts of at least two catalysts.

9. The method according to claim 8, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid is in the range from 1:10 to 10:1.

10. The method according to claim 9, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid ranges from 0.8:1 to 1.4:1.

11. The method according to claim 8, in which the alkene and/or carboxylic acid from the reaction product of the oxidation allocate individually or separately added to the second reaction zone.

12. The method according to any of PP-11, in which the alkane is a ethane, and the corresponding alkene is ethylene, and the corresponding carboxylic acid is acetic acid.

13. The method according to claim 8, in which alkylcarboxylic represents the ethyl acetate.

14. The method according to item 13, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid ranges from 0.8:1 to 1.4:1.

15. The method according to any of PP-14, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level of replacing part of catalyst (catalysts)that are contained in the oxidation reaction zone, less than the least of one or more catalysts with selectivity, non-selectivity of the catalyst (catalysts)in the oxidation reaction zone.

16. The method according to any of PP-15, in which at least one of the at least two catalysts in the oxidation reaction zone comprises molybdenum.

17. The method according to clause 16, in which each catalyst in the oxidation reaction zone comprises molybdenum.

18. United way of obtaining alkenylacyl, which includes the following stages:

(a) introduction into the oxidation reaction zone With2-C4alkane in contact with the containing molecular oxygen gas, and optionally at least one corresponding alkene and water in the presence of at least two catalysts with different selectivity, each of which is effective in the oxidation of the alkane to the corresponding alkene and carboxylic acid, to obtain a product comprising alkene, carboxylic acid and water; and

(b) introducing a second reaction zone at least part of each of the resulting first reaction zone alkene and carboxylic acid containing molecular oxygen gas in mutual contact in the presence of at least one catalyst effective upon receipt of alkenylacyl, obtaining this alkenylacyl,

moreover, in this method, the molar zootoxin is between e obtained in this oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level by controlling in such oxidation reaction zone relative quantities at least two catalysts.

19. The method according to p, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid is in the range from 1:10 to 10:1.

20. The method according to claim 19, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid ranges from 0.8:1 to 1.4:1.

21. The method according to p, in which the alkene and/or carboxylic acid from the reaction product of the oxidation allocate individually or separately added to the second reaction zone.

22. The method according to any of PP-21, in which the alkane is a ethane, and the corresponding alkene is ethylene, and the corresponding carboxylic acid is acetic acid.

23. The method according to p in which alkenylboronic is a vinyl acetate.

24. The method according to p, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid ranges from 0.8:1 to 1.4:1.

25. The method according to any of PP-24, in which the molar ratio between obtained in the oxidation reaction zone with alkene and carboxylic acid regulate or support at a given level of replacing part of catalyst (catalysts)that are contained in the oxidation reaction zone, at least one or a few is Kimi catalysts with selectivity, non-selectivity of the catalyst (catalysts)in the oxidation reaction zone.

26. The method according to any of PP-25, in which at least one of the at least two catalysts in the oxidation reaction zone comprises molybdenum.

27. The method according to p, in which each catalyst in the oxidation reaction zone comprises molybdenum.

28. The method according to any of PP-27, in which the catalyst contained in the second reaction zone includes palladium.

29. The method according to any of PP-28, in which the second reaction zone send additional amount of alkene and alkene from the oxidation reaction zone.

30. The method according to any of PP-29, in which the second reaction zone send additional number containing molecular oxygen gas, and also containing unreacted molecular oxygen gas from the oxidation reaction zone.



 

Same patents:

FIELD: petrochemical processes.

SUBSTANCE: invention relates to improved C2-C4-alkane oxidation process to produce corresponding alkene and carboxylic acid, which process comprises bringing indicated alkane in oxidation reaction zone into contact with molecular oxygen-containing gas and corresponding alkene and optionally with water in presence of at least one catalyst efficient for oxidation of alkane into corresponding alkene and carboxylic acid. Resulting product contains alkene, carboxylic acid, and water, wherein alkene-to-carboxylic acid molar ratio in oxidation reaction zone is controlled or maintained at desired level by way of controlling alkene and optional water concentrations in oxidation reaction zone and also, optionally, controlling one or several from following parameters: pressure, temperature, and residence time in oxidation reaction zone. Invention also relates to integrated process of producing alkyl carboxylate including above-indicated stage of producing alkene and carboxylic acid in first reaction zone and stage of bringing, in second reaction zone, at least part of each of alkene and carboxylic acid obtained in first reaction zone in contact with each other in presence of at least one catalyst effective in production of alkyl carboxylate to produce the same. Invention further relates to production of alkenyl carboxylate including above-indicated stage of producing alkene and carboxylic acid in first reaction zone and stage of bringing, in second reaction zone, at least part of each of alkene and carboxylic acid obtained in first reaction zone plus molecular oxygen-containing gas into contact with each other in presence of at least one catalyst effective in production of alkenyl carboxylate to produce the same.

EFFECT: enhanced process efficiency.

55 cl, 1 dwg, 7 tbl, 22 ex

FIELD: vinyl acetate production by ethane catalytic acetoxylation with acetic acid obtained as intermediate.

SUBSTANCE: claimed method includes: a) bringing gaseous raw material, containing ethane as a main component, into contact in the first reaction zone with molecular oxygen-containing gas in presence of catalyst to obtain the first product stream including acetic acid and ethylene; b) bringing the said first product stream in second reaction zone with molecular oxygen-containing gas in presence of catalyst to obtain the second product stream including vinyl acetate; c) separation the second product stream from stage b) to recovery of vinyl acetate. In the first reaction zone catalyst of general formula MOaPdbXcYd is used, wherein X is at least one element selected from Ti, V, and W; Y is at least one element selected from Al, Bi, Cu, Ag, Au, K, Rb, Cs, Mg, Ca, Sr, Ba, Nb, Sb, Si, and Sn; a, b, c, and d are gram-atom ratio, and a = 1; b = 0.0001-0.01, preferably 0.0001-0.005; c = 0.4-1, preferably 0.5-0.8; and d = 0.005-1, preferably 0.01-0.3. Gaseous raw material from step a) preferably includes ethane and molecular oxygen-containing gas in volume ratio of ethane/oxygen between 1:1 and 10:1, and 0-50 % of vapor as calculated to total volume of starting raw material. Ratio of selectivity to ethylene and selectivity to acetic acid in the first product stream is 0:95-95:0.

EFFECT: integrated technological cycle with controllable product yield while changing technological parameters of the process.

6 cl, 11 ex, 2 tbl, 1 dwg

The invention relates to a method for the synthesis of vinyl acetate in industrial scale

The invention relates to a catalyst for the receipt of vinyl acetate in the fluidized bed

The invention relates to the production of acetic acid
The invention relates to a method for producing vinyl acetate and a catalyst intended for use in this method

The invention relates to a method for producing vinyl acetate from ethylene, acetic acid and oxygen

The invention relates to a vapor-phase process for the preparation of vinyl acetate from ethylene, acetic acid and oxygen-containing gas

The invention relates to a method for producing vinyl acetate from ethylene, acetic acid and oxygen-containing gas

The invention relates to the extraction and reuse of ethylene upon receipt of vinyl acetate in the vapor phase

FIELD: petrochemical processes.

SUBSTANCE: invention relates to improved C2-C4-alkane oxidation process to produce corresponding alkene and carboxylic acid, which process comprises bringing indicated alkane in oxidation reaction zone into contact with molecular oxygen-containing gas and corresponding alkene and optionally with water in presence of at least one catalyst efficient for oxidation of alkane into corresponding alkene and carboxylic acid. Resulting product contains alkene, carboxylic acid, and water, wherein alkene-to-carboxylic acid molar ratio in oxidation reaction zone is controlled or maintained at desired level by way of controlling alkene and optional water concentrations in oxidation reaction zone and also, optionally, controlling one or several from following parameters: pressure, temperature, and residence time in oxidation reaction zone. Invention also relates to integrated process of producing alkyl carboxylate including above-indicated stage of producing alkene and carboxylic acid in first reaction zone and stage of bringing, in second reaction zone, at least part of each of alkene and carboxylic acid obtained in first reaction zone in contact with each other in presence of at least one catalyst effective in production of alkyl carboxylate to produce the same. Invention further relates to production of alkenyl carboxylate including above-indicated stage of producing alkene and carboxylic acid in first reaction zone and stage of bringing, in second reaction zone, at least part of each of alkene and carboxylic acid obtained in first reaction zone plus molecular oxygen-containing gas into contact with each other in presence of at least one catalyst effective in production of alkenyl carboxylate to produce the same.

EFFECT: enhanced process efficiency.

55 cl, 1 dwg, 7 tbl, 22 ex

FIELD: chemical industry; production of synthesis gas, methanol and acetic acid on its base.

SUBSTANCE: the invention is dealt with the methods of production of synthesis gas, production of methanol and acetic acid on its base. The method of upgrading of the existing installation for production of methanol or methanol/ ammonia provides for simultaneous use of the installation also for production of acetic acid or its derivatives. The existing installation contains a reformer, to which a natural gas or other hydrocarbon and a steam (water), from which a synthesis gas is formed. All the volume of the synthesis gas or its part is processed for separation of carbon dioxide, carbon monoxide and hydrogen. The separated carbon dioxide is fed into an existing circuit of synthesis of methanol for production of methanol or is returned to the inlet of the reformer to increase the share of carbon monoxide in the synthesis gas. The whole volume of the remained synthesis gas and carbon, which has not been fed into the separator of dioxide, may be transformed into methanol in the existing circuit of a synthesis of methanol together with carbon dioxide from the separator and-or carbon dioxide delivered from an external source, and hydrogen from the separator. Then the separated carbon monoxide is subjected to reactions with methanol for production of acetic acid or an intermediate compound of acetic acid according to the routine technology. A part of the acetic acid comes into reaction with oxygen and ethylene with formation of monomer of vinyl acetate. With the help of the new installation for air separation nitrogen is produced for production of additional amount of ammonia by the upgraded initial installation for production of ammonia, where the separated hydrogen interacts with nitrogen with the help of the routine technology. As the finished product contains acetic acid then they in addition install the device for production of a monomer of vinyl acetate using reaction of a part of the acetic acid with ethylene and oxygen. With the purpose of production of the oxygen necessary for production of a monomer of vinyl acetate they additionally install a device for separation of air. At that the amount of nitrogen produced by the device of separation of air corresponds to nitrogen demand for production of additional amount of ammonia. The upgraded installation ensures increased production of additional amount of ammonia as compared with the initial installation for production of methanol. The invention also provides for a method of production of hydrogen and a product chosen from a group consisting of acetic acid, acetic anhydride, methyl formate, methyl acetate and their combinations, from hydrocarbon through methanol and carbon monoxide. For this purpose execute catalytic reforming of hydrocarbon with steam in presence of a relatively small amount of carbon dioxide with formation of the synthesis gas containing hydrogen, carbon monoxide and carbon dioxide, in which synthesis gas is characterized by magnitude of the molar ratio R = ((H2-CO2)/(CO+CO2)) from 2.0 up to 2.9. The reaction mixture contains carbon monoxide, water -up to 20 mass %, a dissolvent and a catalytic system containing at least one halogenated promoter and at least one rhodium compound, iridium compound or their combination. The technical result provides, that reconstruction of operating installations increases their productivity and expands assortment of produced industrial products.

EFFECT: the invention ensures, that reconstruction of operating installations increases their productivity and expands assortment of produced industrial products.

44 cl, 3 ex, 6 dwg

Cleaning method // 2237652
The invention relates to an improved method of purification of the reaction products of the process of direct connection, comprising the reaction of ethylene with acetic acid in the presence of an acid catalyst to obtain ethyl acetate, and cleaning products, recycling, and this cleaning method includes the following stages: (I) feeding the reaction product in column (A) to remove the acid from the base which divert acetic acid, and with its top pick at least a fraction comprising boiling components containing, inter alia, hydrocarbons, ethyl acetate, ethanol, diethyl ether and water, and is directed to the apparatus (A1) for decanting in order to share these top shoulder straps on the phase rich in ethyl acetate, and water (rich in water) phase, (II) a separate return at least part of the rich ethyl acetate phase and almost all of the aqueous phase from the apparatus (A1) for decanting as phlegmy in the upper part of the column (A) or near its top, (III) the filing of the rest of the rich ethyl acetate phase from the apparatus (A1) for decanting in the upper part of the Westfalia refinery unit column (s) or near its top, (IV) the removal from the column (C): and nedogona, including significantly refined ethyl acetate, which is directed to the treatment of the colon is his, acetaldehyde and diethyl ether, which is sent to the column to remove aldehyde, and (C) lateral fraction comprising mainly ethyl acetate, ethanol and some water, which is directed to a point below the point of entry is rich in ethyl acetate phase is removed from the column (A), (V) challenging reset, including acetaldehyde, from the top or near the top of the column for removal of aldehyde and return diethyl ether, isolated from the base of the column to remove aldehyde, etherification reactor and (VI) purification of refined ethyl acetate in column (E)

The invention relates to a method for producing acetic acid and/or methyl acetate in the liquid phase, in the presence of carbon monoxide and the catalytic system, and to a method of increasing the stability and lifetime of the catalyst utilized

Synthesis of esters // 2227138
The invention relates to an improved method for producing a lower aliphatic esters, including the interaction of lower olefin with a saturated lower aliphatic monocarboxylic acid, preferably in the presence of water in the vapor phase in the presence of heteropolyanions catalyst, characterized in that the reaction is carried out sequentially placed in several reactors or in one long reactor with several successive layers heteropolyanions catalyst and b) initial reagents practically cleared of metallic impurities or compounds of metals so that before coming in contact with heteropolyanions catalyst metals and/or metal compounds is not more than 0.1 ppm

The invention relates to the production of acetic acid and/or methyl acetate

The invention relates to an improved process for the preparation of butyl acetate by esterification of acetic acid n-butyl alcohol in the presence of an acidic heterogeneous catalyst, separating the resulting reaction water in the form of an azeotrope with azeotropes agent and the selection of the target product, and acetic acid and n-butyl alcohol is fed to the etherification in a molar ratio of 1.00: 1,05, and the process is conducted in two sequential reactors, the first of which is a column type reactor filled with an acidic heterogeneous catalyst, and the second is a reactive distillation reactor, the upper and lower part of which is filled by the nozzle, and the middle part is filled molded cation exchange resin, and in the upper part of the second distillation reactor serves benzene as azeotroping agent

The invention relates to the production of allylacetate high purity based on acetic anhydride

The invention relates to an improved method for producing sec-butyl acetate is used as solvent for paints and varnishes and as raw material for the production of sec-butyl alcohol
The invention relates to the production of acetic acid and/or methyl acetate from a mixture of methanol and methylformate through isomerization and carbonylation

FIELD: petrochemical processes.

SUBSTANCE: invention relates to improved C2-C4-alkane oxidation process to produce corresponding alkene and carboxylic acid, which process comprises bringing indicated alkane in oxidation reaction zone into contact with molecular oxygen-containing gas and corresponding alkene and optionally with water in presence of at least one catalyst efficient for oxidation of alkane into corresponding alkene and carboxylic acid. Resulting product contains alkene, carboxylic acid, and water, wherein alkene-to-carboxylic acid molar ratio in oxidation reaction zone is controlled or maintained at desired level by way of controlling alkene and optional water concentrations in oxidation reaction zone and also, optionally, controlling one or several from following parameters: pressure, temperature, and residence time in oxidation reaction zone. Invention also relates to integrated process of producing alkyl carboxylate including above-indicated stage of producing alkene and carboxylic acid in first reaction zone and stage of bringing, in second reaction zone, at least part of each of alkene and carboxylic acid obtained in first reaction zone in contact with each other in presence of at least one catalyst effective in production of alkyl carboxylate to produce the same. Invention further relates to production of alkenyl carboxylate including above-indicated stage of producing alkene and carboxylic acid in first reaction zone and stage of bringing, in second reaction zone, at least part of each of alkene and carboxylic acid obtained in first reaction zone plus molecular oxygen-containing gas into contact with each other in presence of at least one catalyst effective in production of alkenyl carboxylate to produce the same.

EFFECT: enhanced process efficiency.

55 cl, 1 dwg, 7 tbl, 22 ex

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