Method of oxidative dehydration with improved regulatibility for obtaining butadiene

FIELD: chemistry.

SUBSTANCE: one of the process variants comprises the steps of providing a butene-enriched hydrocarbon feed, evaporating and superheating said butene-enriched hydrocarbon feed at a temperature of at least about 345°C (650°F), mixing said butene-rich hydrocarbon feed with superheated steam and oxygen-rich gas to form a reactor feed stream; providing a catalytic bed of oxidative dehydrogenation catalyst pellets, passing mentioned reactor feed stream from the inlet through said catalyst bed and forming a stream of a butadiene-rich product; providing a catalytic bed of oxidative dehydrogenation catalyst pellets, passing mentioned reactor feed stream from the inlet through said catalyst bed and forming a stream of a butadiene-rich product; providing mentioned catalytic oxidative dehydrogenation catalyst bed with a plurality of temperature sensing devices associated therewith for measuring the temperature in the bed in the direction of flow; controlling the inlet conditions of mentioned reactor such that oxidative dehydrogenation reactions initially take place in the layers of mentioned oxidative dehydrogenation catalyst most remote from said inlet, including reacting interaction with reactor feed stream with mentioned catalyst in the reaction zone and forming a butadiene-rich product stream; controlling the temperature over the length of the bed and occasionally increasing the temperature at the inlet so that the reaction zone migrates relative to said inlet in said oxidative dehydrogenation catalytic bed.

EFFECT: use of the proposed invention avoids the effects of oxygen leaking into the catalyst.

20 cl, 6 tbl, 8 dwg

 



 

Same patents:

FIELD: chemistry.

SUBSTANCE: described is a catalyst for producing ethylene or propylene which contains ruthenium oxychloride RuOxCl4-2x, deposited on a support, where x is greater than 0 but less than 2. The support is titanium oxide or tin oxide. The process is carried out at 200-250°C, and the catalyst used is the catalyst described above. The process is carried out in a flow reactor.

EFFECT: improved catalyst selectivity and low temperature of the process of oxidative dehydrogenation of ethane to ethylene and propane to propylene.

5 cl, 9 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing ethylene via oxidative dehydrogenation of ethane in a gaseous mixture of oxygen and ethane at high temperature in the presence of a mixed oxide catalyst of the composition Mo1.0V0.37Te0.17Nb0.12O3 in a flow reactor. The reactor further includes a selective carbon monoxide oxidation catalyst, which is gold or rhodium on a titanium dioxide support, with the following ratio of components, wt %: gold 0.05-0.3, rhodium 0.5-1.0 and titanium dioxide - the balance, wherein the mixed oxide catalyst is located at the gaseous material inlet, and the selective carbon monoxide oxidation catalyst is located further downstream of the gas stream and the catalysts are taken in volume ratio of 80-90 and 20-10, respectively.

EFFECT: use of the disclosed method enables to achieve high conversion of oxygen, which facilitates further separation of ethylene from the reaction mixture and also makes reaction gaseous mixtures less explosive; the proposed volume ratio of catalysts loaded into the reactor enables to combine two reactions in a single process to obtain ethylene with a minimum amount of undesirable impurities.

4 cl, 4 ex, 1 tbl

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing ethylene, which includes a step for oxidative condensation of methane in a gaseous mixture at atmospheric pressure and high temperature in the presence of a catalyst containing manganese and sodium tungstate on a silicon oxide support. The a catalyst which further contains cerium oxide is used at the step for oxidative condensation of methane, with the following ratio of components, wt %: manganese 1-2, sodium tungstate 3-5, cerium oxide 3-4 and silicon oxide - the balance, and the process is carried out in a flow-type double-deck reactor by contacting a fixed catalyst bed for oxidative condensation of methane, located on the upper deck of the decked reactor and heated to 750-800°C, with a methane-air mixture or methane-oxygen mixture in the ratio CH4/O2=4-7/1, with volume rate of feeding the gaseous material of 1000-5000 h-1,followed by mixing the formed reaction gases heated to 750-800°C, said gases containing an ethane-ethylene fraction with an additional amount of cold air fed into the space between the decks, and the obtained gaseous mixture with ratio C2H6/O2=2/1 is fed into the lower deck of the reactor and contacted with a catalyst for oxidative dehydrogenation of ethane located therein, which is a mixed oxide composition of the formula Mo1.0V0.37Te0.17Nb0.12O3, heated to 380-420°C.

EFFECT: use of the present method enables to achieve high selectivity and efficiency with respect to formation of ethylene while simultaneously reducing power consumption.

3 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of regenerating a catalyst layer and a method of producing acrolein and/or acrylic acid via heterogeneously catalysed partial gas-phase oxidation of propylene. The method of regenerating a catalyst layer which is deactivated during heterogeneously catalysed partial dehydrogenation of a hydrocarbon involves passing a regenerating gas through a layer of deactivated catalyst for a period of time t, said gas being at high temperature and containing molecular oxygen and an inert gas but not containing a hydrocarbon, under the condition that during the regeneration process total content GA of carbon oxides in the regenerating gas passed through the catalyst layer at the outlet of the catalyst layer within a period of time t at least periodically exceeds total content GE of carbon oxides in the regenerating gas passed through the catalyst layer at the inlet of the catalyst layer, wherein the corresponding content values are expressed as a percentage of the volume (vol. %) of the regenerating gas and wherein the difference ΔG=GA-GE before the end of the regeneration process passes through a maximum ΔGmax, where: a) 0.2 vol. % ≤ ΔGmax≤ to 5 vol. %, and b) content of molecular oxygen in the regenerating gas to be passed through the catalyst layer expressed in vol. % of the regenerating gas, for a period of time t before the end of the regeneration process, is increased at least thrice, wherein the increase in content of molecular oxygen each time is at least 2 vol. %. In the method of producing acrolein and/or acrylic acid, the catalyst layer is regenerated using the disclosed regeneration method from time to time.

EFFECT: susceptibility of the regenerated catalyst layer to deactivation is not different from susceptibility of a freshly loaded catalyst to deactivation.

22 cl, 3 tbl, 4 dwg, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method for continuous, heterogeneously catalysed partial dehydrogenation of at least one dehydrogenated (C2-C4)-hydrocarbon in gas phase, comprising a procedure where at least one initial gas stream is continuously fed into a reaction space surrounded by jacket which touches the reaction space and has at least one opening for inlet of at least one initial gas stream in the reaction space and at least a second opening for outlet of at least one stream of the formed gas from the reaction space, said initial gas stream containing at least one dehydrogenated hydrocarbon; in the reaction space at least one dehydrogenated hydrocarbon passes through at least one layer of catalyst lying in the reaction space to obtain a gaseous product which contains at least one dehydrogenated hydrocarbon which does not react with the dehydrogenated hydrocarbon; and using an oxidative or a non-oxidative method, molecular hydrogen and/or water vapour are partially dehydrogenated to form at least one dehydrogenated hydrocarbon; at least one stream of the formed gas is continuously removed from the reaction space; the method is characterised by that the surface of the jacket on the side in touch with the reaction space is made from steel S, partially in a layer of thickness d equal to at least 1 mm, said steel having the following composition: from 18 to 30 wt % Cr (chromium), from 9 to 36 wt % Ni (nickel), from 1 to 3 wt % Si (silicon), from 0.1 to 0.3 wt % N (nitrogen), from ≥ 0 to 0.15 wt % C (carbon), from ≥ 0 to 4 wt % Mn (manganese), from ≥ 0 to 4 wt % Al (aluminium), from ≥ 0 to 0.05 wt % P (phosphorus), from ≥ 0 to 0.05 S (sulphur) and from ≥ 0 to 0.1 wt % one or more rare-earth metals, and in the rest Fe and impurities due to the synthesis process, where the percentages are associated with total weight, respectively. The invention also relates to a jacket in which the disclosed method is realised.

EFFECT: use of the present invention enables to reduce catalysed thermal decomposition of dehydrogenated hydrocarbon and/or a hydrocarbon capable of being dehydrogenated.

30 cl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to methods of producing ethylene, and ethylene and acetic acid from initial gas containing ethane and oxygen when said gas gets into contact with a MoaVvTaxTeyOz catalyst, in which a equals 1.0, v ranges from approximately 0.01 to approximately 1.0, x ranges from approximately 0.01 to approximately 1.0, y ranges from approximately 0.01 to approximately 1.0 and z is the number of oxygen atoms required to transform the catalyst into an electrically neutral state.

EFFECT: use of the methods enables to obtain said products with high selectivity and high output in a single step in unit time under reaction conditions.

30 cl, 2 tbl

FIELD: chemistry.

SUBSTANCE: present invention pertains to perfection of the method of obtaining at least, one product of partial oxidation and/or ammoxidising of propylene, chosen from a group, comprising propylene oxide, acrolein, acrylic acid and acrylonitrile. The starting material is raw propane. a) At the first stage, raw propane, in the presence and/or absence of oxygen, is subjected to homogenous and/or heterogeneous catalysed dehydrogenation and/or oxydehydrogenation. Gas mixture 1, containing propane and propylene is obtained. b) If necessary, a certain quantity of the other components in gas mixture 1, obtained in the first stage, besides propane and propylene, such as hydrogen and carbon monoxide is separated and/or converted to other compounds, such as water and carbon dioxide. From gas mixture 1, gas mixture 1' is obtained, containing propane and propylene, as well as other compounds, besides oxygen, propane and propylene. c) At the third stage, gas mixture 1 and/or gas mixture 1' as a component, containing molecular oxygen, of gas mixture 2, is subjected to heterogeneous catalysed partial gas-phase oxidation and/or propylene, contained in gas mixture 1 and/or gas mixture 1', undergoes partial gas-phase ammoxidising. Content of butane-1 in gas mixture 2 is ≤1 vol.%. The method increases output of desired products and efficiency of the process.

EFFECT: increased output of desired products and efficiency of the process.

72 cl, 10 ex

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

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: chemistry.

SUBSTANCE: invention relates to method of dehydration of alkanes with balancing product composition. Gaseous flow of substance, which contains alkanes, is passed in continuous mode through catalyst layer, located in from two to 10 successfully connected reactors of adiabatic, allothermic or isothermic type or in their combination, which results in formation of gaseous flow, containing olefin, hydrogen and alkane which has not reacted, with at least one reactor being adiabatic one, which oxygen is supplied to. At least one of the process parameters: temperature, pressure or ratio of vapour and hydrocarbons is registered in one or more points on at least one of reactors in form of measured values, at least one of the process parameters is purposefully controlled and subjected to impact so that composition of produced gas at output of at least one of reactors remains constant during operation time. Invention also relates to application of said method for dehydration of particular hydrocarbons.

EFFECT: application of claimed method makes it possible to obtain product with constant composition at the output from reactor during the entire operation time.

15 cl, 1 tbl, 5 ex, 8 dwg

FIELD: chemistry.

SUBSTANCE: catalyst is characterised by the following content of components: 30-70 wt % (Mo5-12Sb>6.0-15Bi0.2-3M10.1-10M20.05-0.5M30.01-2On) and 70-30 wt % SiO2, where M1 is one or more elements selected from Co, Ni, Fe, Cr, Cu; M2 is one or more elements selected from Na, K, Cs, Mg, Ce, La, M3 is an element selected from P, B, n is a number defined by the valence and number of elements other than oxygen. The invention also relates to a method of producing butadiene-1,3 using said catalyst.

EFFECT: catalyst enables to achieve high butadiene selectivity in oxidative dehydrogenation of n-butenes and provides high output of butadiene.

3 cl, 1 tbl, 7 ex

FIELD: chemistry.

SUBSTANCE: invention relates to methods of producing catalysts for the butadiene synthesis process. Described is a catalyst for producing butadiene by converting ethanol, which contains zinc, silicon, magnesium and aluminium compounds. The catalyst further contains calcium and/or strontium compounds. The composition of the catalyst, including oxides, is as follows, wt%: magnesium oxide 47-76, aluminium oxide 4.5-12.5, zinc oxide 0.1-1.5, calcium oxide and/or strontium oxide 1.5-7.5, silicon dioxide - the balance. The catalyst may contain oxides and/or compounds of barium and/or titanium and/or tin, which are easily decomposed to oxides, in amount of 0.5-5.0 wt% and/or portland cement in amount of 1-20 wt%.

EFFECT: high conversion of ethanol and butadiene selectivity.

3 cl, 1 tbl, 5 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method for simultaneous production of aromatic hydrocarbons and divinyl via catalytic conversion of bioethanol flowing on a zeolite-containing catalyst HZSM-5 at temperature of 390-420°C, volume rate of the liquid hydrocarbon of 2-4 h-1. The method is characterised by that in order to increase output of divinyl in the contact gas, a layer of a K2O-ZnO/γ-Al2O3 catalyst is placed over the layer of the HZSM-5 catalyst with weight ratio of the layers of (0.5-1):1 and the following content of components of the top layer: K2O - 0.1-0.25%, ZnO - 22-24%, γ-Al2O3 - the balance. The process is carried out in the presence of a hydrogen peroxide initiator, taken in amount of 1 wt % in the starting bioethanol.

EFFECT: method increases selectivity of the process of converting bioethanol and particularly enables to simultaneously obtain high content of divinyl in the gaseous phase and aromatic hydrocarbons in the liquid phase.

2 cl, 4 ex

FIELD: chemistry.

SUBSTANCE: starting ethanol, which is fed to the synthesis step, contains acetaldehyde and/or water in amount of not more than 50 wt %; the catalyst further contains a calcium and/or strontium compound, with the following content of components, with respect to oxides, wt %: magnesium oxide 47-76, aluminium oxide 4.5-12.5, zinc oxide 0.1-1.5, calcium oxide and/or strontium oxide 1.5-7.5, silicon dioxide - the balance. Synthesis is carried out on a fixed granular catalyst bed.

EFFECT: method provides technological flexibility of the process, high conversion of ethanol and butadiene selectivity and prolongs the synthesis process or enables to carry out the process continuously.

7 cl, 1 tbl, 10 ex

FIELD: chemistry.

SUBSTANCE: invention relates to petrochemical industry and specifically to catalytic processing of bioethanol into valuable petrochemical products, particularly high-molecular weight aromatic hydrocarbons. The technical result is achieved due to that catalytic conversion of ethanol or an ethanol-butanol mixture (3:1) is carried out at temperature of 400-420°C, volume rate of feeding low-molecular weight alcohols on liquid material of 2 h-1 on a zeolite-containing catalyst of the following composition: ZnO - 1-2 wt %; γ-Al2O3 - 6-7 wt %; K2O - 0.05-0.1 wt %; MgO - 2-3 wt %; SiO2 - 2-3 wt %; HZSM-5 - the balance. The bioethanol conversion reaction is carried out in adiabatic continuous flow reactors. The bioethanol conversion products are hydrogenated in an autoclave-type reactor with volume of 250 cm3 at 250-300°C and 10 MPa.

EFFECT: high selectivity of the process of converting bioethanol and simultaneous production of divinyl in gas phase and aromatic hydrocarbons in liquid phase.

1 cl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method (versions) of producing divinyl by converting ethanol in the presence of an oxide catalyst, containing zinc oxide and γ-aluminium oxide, characterised by that the catalyst further contains calcium oxide, silicon dioxide and magnesium oxide, with the following initial composition in wt %: ZnO - 25-35, SiO2 - 3-5, MgO -3-5, K2O - 1, γ-Al2O3 - the balance. The other version of the invention employs the same catalyst, but ethanol is converted via chemical initiation in the presence of hydrogen peroxide, taken in an amount which ensures content thereof in ethanol of 0.8-1.5 wt %.

EFFECT: use of the present invention increases selectivity of the process with respect to divinyl, output of the product per cycle and efficiency of the catalytic process overall.

2 cl, 1 tbl, 6 ex

FIELD: blasting.

SUBSTANCE: invention relates to a method for joint production of isobutene and butadiene by dehydration of C4-hydrocarbons on a chromia-alumina catalyst at higher temperature with further separation of finished products of dehydration by methods of absorption-desorption and extractive rectification and release of commercial isobutene and butadiene -1,3. At the same time the method is characterized by the fact that C4-hydrocarbons are a mixture of hydrocarbons of the following composition, wt %: isobutane 15÷45, n-butane 15÷60, n-butenes 20÷45.

EFFECT: using this method makes it possible to produce isobutene and butadiene in one reactor with high yields.

1 cl, 1 tbl, 4 ex

FIELD: chemistry.

SUBSTANCE: invention refers to the method of separating and purification of 1,3-butadiene from the mixture consisting mainly of C4-carbohydrates and containing 1,3-butadiene and C4-carbohydrates that differ from the former by the number of unsaturated bonds and/or α-acetylene protons including at least (an) area(s) of extractive rectification with the polar extractant, denudation and ordinary rectification that is characterized by the fact that at least a polar spirit with the boiling point over 120°C is used as the mentioned extractant; stripping of C4-carbohydrates from the areas of extractive rectification and denudation of the mentioned extractant is performed under the high pressure from 3.5 to 6.5 at, at least into the lower part and/or into the boiler(s) of the extractive rectification area(s) the carbohydrate intermediate desorbent with the boiling point from 27 to 85°C is introduced in the amount that provides its content in the cube(s) of the high pressure denudation area(s) from 3 to 30 % weight; then the intermediate desorbent is stripped from the greater part of the extractant in the low pressure denudation area with 1.0-2.0 at; the extractant is fed back to the upper part of the extractive rectification area(s) and the intermediate desorbent to at least the mentioned point(s) of extractive rectification, and 1,3-butadiene undergoes additional purification from chemical impurities by means of rectification, supposedly with the small amount of extractant.

EFFECT: reduction of losses of 1,3-butadiene and improvement of the processing and economical efficiency.

10 cl, 3 tbl, 3 ex, 3 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a single-step method for gas-phase production of butadiene, involving conversion of ethanol or a mixture ethanol and acetaldehyde in the presence of a catalyst, characterised by that the reaction takes place in the presence of a solid-phase catalyst containing a metal selected from: silver, gold or copper, and a metal oxide selected from magnesium, titanium, zirconium, tantalum or niobium oxide.

EFFECT: method provides high output of butadiene, selectivity of the process and high degree of conversion of material.

6 cl, 23 ex, 1 tbl

FIELD: catalysts of selective hydrogenation of alkynes of C4 fractions.

SUBSTANCE: proposed catalyst contains 1-30 mass-% of copper used as first active component, 0.001-5 mass-% of palladium used as second active component, at least 0.001-6 mass-% of one metal selected from Al, Pt, Pb, Mn, Co, Ni, Cr, Bi, Zr and Mo as co-catalyst; the remainder being one carrier selected from aluminum oxide, silicon dioxide and titanium oxide. Method of production of catalyst includes impregnation of carrier calcined preliminarily with solutions of active components depending on their content in catalyst. Alkynes are removed from C4 fractions enriched with alkynes by means of selective hydrogenation with the use of said catalyst.

EFFECT: enhanced selectivity and stability of catalyst.

31 cl, 2 tbl, 13 ex

Up!