Cleaning method

 

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 sent to clear the past other things, 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). Cleaning method allows you to remove acetaldehyde impurities present because acetaldehyde has a negative impact on the catalyst of esterification. 2 N. and 26 C.p. f-crystals, 13 tab., 1 Il.

The present invention relates to a method for producing esters direct-attach lower saturated carboxylic acid to the olefin in the presence of a catalyst and to a method of cleaning cycle flows returned to the process for renewal of activity and longer catalyst life.

Production of esters such as ethyl acetate or n-butyl acetate, the reaction of esterification, respectively, ethanol or n-buta in GB-A 1438410. It is also known the production of esters, such as those mentioned above, the addition of acid to the olefin. When carrying out the method of producing ethyl acetate direct connection of acetic acid to ethylene get a number of by-products and impurities. Although some of the major by-products similar to those removed from acetic acid ethyl ester obtained by the esterification of acetic acid (e.g., ethanol and diethyl ether), this method has significant differences and, therefore, it receives a number of quite other by-products and impurities. In particular, since one of the reactants is ethylene, the possibility exists for its oligomerization, which produces a number of by-products, including but not limited to hydrocarbons in the range from ethane and butane to more long-chain hydrocarbons with 10-12 or more carbon atoms. These by-products can include both saturated and unsaturated hydrocarbons and may also contain oxidized compounds. It is known that during the reaction of the direct connection over time there has been some gradual deactivation of the catalyst, and one of the reasons of this phenomenon concluded so far in the threads of the reaction products direct accession no aromatic compounds were not found.

With the aim to reduce to a minimum such deactivation of the catalyst was removed during the process of direct attachment to apply the method of cleaning product, which includes stages of distillation and return to the process. Distillation scheme includes mainly the first column, which serves liquid reaction products attach (via separators single equilibrium evaporation) and from which divert excess/unreacted acetic acid and heavy shoulder straps, the second column from which divert light shoulder straps, ethanol and water to obtain an ethyl acetate crude product, a third column in which water is separated alcohol (and the entire ethyl acetate) to recovery of the alcohol to return to the process, and the fourth column, which removes any residual by-products selected as azeotrope, for example, with water, from the top of the second column, and medium-chasing who squeezed from the base of the column, rafinuyut and purify the crude ethyl acetate, taken from the second column. However, in designs that were used up to the present time, there is no means for removing the formed during the reaction of the aldehyde by-products (which, as you know, call the RA occurs as stated above, due to coking of aromatics or olefins.

It was found that the ratio of ethyl acetate, obtained by direct reaction of accession, this distillation scheme can be specially modified not only to remove impurities, the new series characteristic of the process of direct connection, but also to ensure such quality cycle products, which is enough to prevent the reduction of the activity or reducing the service life of the catalyst.

Thus, the invention features a 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 a catalyst to obtain ethyl acetate and purification recycle products, and this cleaning method includes the following stages (see attached drawing):

(I) feeding the reaction product in column (A) to remove the acid from the base which divert acetic acid, and from the top of which take at least a faction, consisting of 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 fazlollahi 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) feeding 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 column (E)

(b) taken from the top of the column of product, including boiling components containing, inter alia, 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, in etherification-s reactor

(VI) purification of refined ethyl acetate in column (E).

For this reaction accession as a catalyst, it is advisable to use an acid catalyst, which may be selected from postinoculation, phosphonoacetate and heteropolyanions catalysts. Preferred g is applied, is silicon dioxide, which may be a material of any configuration or be in the form selected from the group including balls, agglomerates of spheres, powder, extrudate, and granules. Specific examples of the silica include, but are not limited to, silicon dioxide Degussa (Aerosil) 350 (manufactured by Degussa) and silica varieties Grace 57 (manufactured by W. R. Grace). The reaction may be carried out with the use of technical acetic acid, which may include some amount of diethyl ether which is separated from the reaction products and return at this stage.

The following table presents the typical composition of the reaction products of the process of direct connection, which is used as source material for columns (A) remove the acid. Depending on the length of the catalyst and method of conducting the process, the relative concentrations of the components varies. The following table 1 presents a picture that is observed at the present time.

Below is a description of the technological scheme of the cleaning sections in the form of distillation in the process of producing ethyl acetate by the method premultiplied a column (A) to remove acid, in which the product which is separated from the reagent acetic acid and heavy straps". At least part of the acid, water and heavy straps from the base of the column (A) can be removed in the form of the cubic reset from the base or near the base of the column (A), and optionally you can pass through the ion-exchange layer (for example, cation exchange) resin to remove dissolved/suspended metals released from the corrosion, and then departing from it, the eluate can be sent to an evaporator to obtain a recycle of acetic acid, which in turn can be mixed with fresh acetic acid and then used to saturate the ethylene reactant introduced into the reactor. From the top of the column select at least faction, including, without limitation, 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 (i.e., rich in water) phase. Next withdrawn from column (A) the product is fed to the column (C) refining ethyl acetate, from the top of which is in the form of a distillate obtained by the distillation of the product selected volatile material, comprising mainly diethyl ether, acetaldehyde aldehyde, which by the distillation of diethyl ether in the form of distillate remove acetaldehyde.

The greater part faction with diethyl ether containing some other boiling components withdrawn from the Foundation of the aldehyde column, return to the reactor as recycle stream, but a small proportion of this fraction being squeezed out of the process. This avoids the accumulation of boiling components. From the column (S) in the form of lateral fraction advisable to remove the ethanol and water (together with some ethyl acetate), and after cooling, it is advisable to send in the mixer, which may be a static mixer, with the aim to ensure homogeneous mixing and matching, then this homogeneous mixture is fed to the device (C1) for decanting that allows you to separate an organic phase comprising ethyl acetate, the aqueous phase comprising ethanol, optionally after one or more stages of this washing the organic phase with water to remove ethanol together with the washing water in the aqueous phase. The separation of both phases can be facilitated by use of in-situ apparatus for decanting, such as Poppet nozzle. The aqueous phase, which contains most of the ethanol, Celesio the base can be selected fraction, comprising essentially water. The organic phase contains small concentrations of the aqueous phase, which exists as a separate phase, and the acceptable content of this aqueous phase in the organic phase as a whole is less than 1000 ppm million, preferably less than 300 ppm million, as a rule, about 90-220, if in the future the value of the column (S) will not change and does not "outweigh" the benefits of reducing this concentration to that which is below the specified level. The aqueous phase, which slips in an ethyl acetate phase can be reduced by regulating the length of stay of a homogeneous mixture within the apparatus for decanting and/or using the in-situ apparatus for decanting. The organic phase is separated from the apparatus (C1) for decanting, it is advisable to return in column (C), preferably at a point that is directly below the point of diversion of a side fraction from the above column (C). From the base of the column (C) divert the crude ethyl acetate, which is advisable to send in column (E) for the purification of ethyl acetate. The function of the column (E) is the allocation of the flow of crude ethyl acetate a number of secondary straps and all heavy uglevodoroy concentrate and displace from the base of the column (E). Cleared an ethyl acetate product is taken from the top of the column (E). If necessary, further purification/treatment of ethyl acetate, taken from column (E), it can pass through a number of additional optional treatment layers/columns.

Fluid exiting low pressure system for a single equilibrium evaporation, arrives in column (A) to remove the acid, the function of which consists in the separation from the product stream of acetic acid and all heavy hydrocarbons. This column may operate under atmospheric or elevated pressure.

In this case the separating capacity of the columns was determined in accordance with the present invention either as the number of actual experimental plates (with appropriate efficiency of the plates), or as the number of theoretical stages needed for the separation. The results of these definitions are interchangeable, provided that the efficiency of plate distillation columns used [or the height equivalent to a theoretical plate (WATT) if you use a Packed column] known. In this example, column (A) worked under atmospheric pressure and included 53 plates (with efficiency of approximately 50%, which corresponded to a total of 27 those who attny product, that was the ethanol and/or water azeotrope, and all boiling components passed through the head of the column (A) in the form of upper straps, which are condensed and sent to a device for decanting, which is appropriately cooled and who worked at 40C. At this stage the upper shoulder straps were divided into two phases, one of which was rich in ethyl acetate, and the other was the water phase was rich in water). Column (A) worked at a rate of reverse flow of organic material of 0.5:1 (taking into account internal irrigation, the total coefficient of reverse flow of organic material was probably 1:1), resulting in column (A) return half of the organic product. As phlegmy return all of the aqueous phase. Although it also contributed to the separation in column (A), the aqueous phase consisted of relatively large amounts of acetaldehyde. If this aqueous phase is sent directly to the column (D) purification of water in the reactor with ethanol inevitably would return acetaldehyde. This should be avoided because of the undesirable effects of acetaldehyde on the catalyst. Return the aqueous phase in this way in the form of phlegmy supply just acetaldehydes two alternative mode of operation of the column (A). They are the work of a column either (a) in the fill mode by ethyl acetate, or (b) in the mode of filling up with water. The first mode (a) the usual esterification, because the water in the base of the column (A) is an important regulatory variable factor. Its contents must be maintained at a low level, and this means that the work column (A) in the fill mode water would be impossible. It was found that column (S) can operate in either mode, but the mode of filling with water gives a great advantage in that there is a possibility that the process largely without organic phlegmy that allows you to reduce capital expenditures and technology spending. In more detail these two modes of operation (under atmospheric pressure), respectively, are presented in the following tables 2-5.

A. Fully an ethyl acetate mode

The entire ethylene and all low-boiling hydrocarbons entering the system, can be identified in column (A) and remove the top straps. In the above conditions was observed with the following temperature profiles are presented in the following table 3.

B. Mode with filling water

In contrast to that is h (A), in which the middle section of the column (A) fill with fluid, which essentially consists of water. This means that the acid is displace in the lower part of the column (A), and the ethyl acetate is in its upper part. Column (A) can operate with a smaller number of phlegmy than is necessary for the regime filled with ethyl acetate, which gives the possibility to reduce the minimum flow of water vapor.

The composition of the materials in this mode of operation, which was carried out in the experiment with 37 theoretical stages, are presented in the following table 4.

The temperature profile of the column (A) shown in table 5.

Ion-exchange layers and the evaporator

To remove impurities from a liquid comprising unreacted acid, water and heavy shoulder straps allocated from the base of the column (A), you can use an optional layer of ion-exchange resins, and before passing through this optional layer of ion exchange resin capable of removing released from the corrosion of dissolved/suspended metals and forming the eluate, which includes acetic acid and water, this liquid is advisable to apply to the coagulator to remove all ionoobmennoi resin layer, it is advisable to use a cationic ion-exchange resin, such as PuroliteCT145 (Purolite company) or AmberlystA16 (firm Rohm and Haas). These resins relative to the rack at a temperature that is created at the base of the column (A). Fluid is directed into these layers of resin for the removal of all metals, which can dissolve in acid reagent due to corrosion when in column (A) passes the acid. Such metals released from the corrosion, known as catalyst poisons, so this stage helps to protect the reactor and the catalyst from all occupied metals passing through the upper part of the evaporator, thereby reducing the risk of deposition of heavy metals on the catalyst.

Further, the liquid waste from layers of resin (i.e., the eluate), served on the 2nd from the top plate of the evaporator, including 5 plates (efficiency of the plates about 50%) and ethylene reagent directed to the basis of the same evaporator, thanks to evaporate entered him in acid and recycle all materials. Featured evaporator includes liquid demister, which is located at the level of the top plate or the top and minimizes any transfer fluid. Above the upper plate of the evaporator it is expedient to introduce fresh acetic KIS is any transfer of heavy metals together with the vaporized acid and ethylene. This way you can reduce the need for layers of resin.

The presence of the evaporator also gives the opportunity to solve the problem of providing all the heavy straps that are contained in the recycle acid. They are concentrated at the base of the evaporator together with a certain amount of acid and can be expelled from the system at a rate of approximately 83 kg/h

Before feeding into the reactor for the reaction of direct attachment ethylene, coming from the evaporator and saturated vaporized acid (and possible water), can be optionally heated.

Acceptable reactor for the reaction of direct attachment includes four adiabatic reactor with a fixed bed, a preferred construction which provides radial expiration. Usually exothermic effect depends on the amount of catalyst in each layer, but when passing through each catalytic layer it usually is 5-15C., for example approximately 8-8,5C. the Reaction proceeds in the vapor phase, and the acceptable temperature at the inlet of the reactor or each reactor is approximately 175C, although it can vary depending on the state of the catalyst.

To maintain the ratio between the ethylene and acid at the insertion point in the temperature of the gases, sent to the next reactor in this sequential system, these reactors can add water.

For the recovery of that amount of heat, which is suitable from a practical point of view, you can perform the heat exchange between the gases exhaust from this reactor, and a gas stream originating from the above-mentioned evaporator, and then use the heat as an energy source to maintain the boil in column (E) for the purification of ethyl acetate, which is described below, and, finally, to heat the gas entering the evaporator. The cooled gases in the reactor, optionally cooled for condensation of liquids prior to their entry into the system of the separation of liquids/gases, which is recommended to apply the high pressure separator for separating steam and liquid phases (hereinafter "SVDPR"), which operates under high gauge pressure, for example about 1100 kPa (10 bar). This allows you to remove the top of the shoulder strap light vapor fraction total unreacted ethylene and return in a production line. During the return of ethylene returned to the evaporator through the compressor and discharge, derive from this recycle stream order n is an ode. The purpose of cooling the source of the material sent in SVDPR, is firstly, to separate the bulk of the resulting acid and ethyl acetate from the non-condensable source components and by-products. The purpose of cooling these products to the lowest possible temperature is to be kept to the minimum number of carry out with the upper shoulder strap acetaldehyde and to the maximum amount of exhaust acetaldehyde. Himself SVDPR could be subject to rapid cooling, thus ensuring capture in SVDPR just acetaldehyde stream of liquid withdrawn from the Foundation of SVDPR. The flow of liquid remaining in SVDPR, is sent to the low pressure separator for separating steam and liquid phases (hereinafter "CNDPS"), which operates under a gauge pressure of 200 kPa (1 bar) and at approximately 40C. Thus, everything in this thread gases are removed as the top product, and this gaseous stream of the upper ring may be washed in order to further ensure the removal of all contained acetaldehyde. Liquid waste from CNDPS, is injected into the column (A) recovery of acetic acid from ethyl acetate, ethanol and all about is the highlight from the base of the column (A), which is recommended at about 138C. and under a gauge pressure of approximately 320 kPa (2.2 bar), together with all the heavy impurities and the material returns to the evaporator to acid. Top zipper liquid from the column (A) for the recovery of acid consists of two phases (aqueous and organic) so to separate these two phases may be used in apparatus for decanting. The aqueous phase can be returned in column (A) in the form of phlegmy and eventually be removed from the base of the column together with the acid. The organic phase can be partially returned in the form of phlegmy in column (A), but it emit mainly in the form of the head of a shoulder strap as the product of the column and pumped to the column (C) refining of ethyl acetate, which is described below. The flow of the distillate from column (C) refining ethyl acetate guide, as described below, in the column for the removal of acetaldehyde.

Column (C) refining ethyl acetate

Exhaust from the apparatus (A1) for decanting is rich in ethyl acetate phase containing all boiling impurities, including but not limited to, acetaldehyde and diethyl ether, was filed on 12th top-level columns (C) refining of ethyl acetate, which included 48 theoretical stages and RUB the function of this column were removed from the stream of products of ethanol, water and boiling impurities. Ethanol and water together with a certain quantity of ethyl acetate was removed from the column with 20-th stage in the form of a side faction. Next, the ethanol was washed from the stream using water that is introduced into a static mixer located downstream of the above apparatus for decanting, with a flow rate of 9500 kg/h (in order to ensure the ratio between expenditure flows of organic and aqueous phases, expressed in kilograms per hour, about 8.5 to 9.5:1) and at 40C was carried out by the decantation. An ethyl acetate phase was returned to the column, introducing her to the point, which was immediately under the sash side of the faction. The aqueous phase containing ethanol, was added in column (D).

The insertion point of the source material in column (C) was much higher sash side faction, which allowed to avoid the washing apparatus for decanting all boiling components and primarily acetaldehyde, because the organic matter that falls in this thread, showed a tendency to subsequent return through column (D) in the reactor. Thus, boiling components accumulates in the upper section of the column (S) and removed as stream head straps. All ethylene is (C) and the top of the ring was returned to the reactor through a separator to separate the steam and liquid phases, thanks ensured condensation and re-feed to a distillation section just acetaldehyde contained in this thread. A typical composition of various materials withdrawn from column (C) presents the following table 6.

The temperature profile for column (C) presents the following table 7.

When the reactor operates in this mode, in which impurities in the form of secondary straps are formed at low concentrations, there is a possibility to bypass columns (E) and saving of water vapor, the consumption of which is associated with the work column (E) purification of ethyl acetate. In these circumstances, an ethyl acetate product can be defined as a side fraction from a point near the base of the column. In this case, less volatile heavy hydrocarbons are not treated in column (E), and replacing in the form of fraction withdrawn from the base of the column (S). In this embodiment, the material withdrawn from the base of the column (S) becomes the product.

Column for removal of acetaldehyde

The upper shoulder straps from the column (s) was filed on 4th top notch small columns for removal of acetaldehyde, which included 10 theoretical stages. The volatile nature of metaldehyde under high gauge pressure, equal to at least 400 kPa (at least 3 bar), and when the molar ratio of the reverse flow of 26:1. In order to ensure more effective removal of all inert components, if they are still available, the process in this column can be carried out at a gauge pressure of up to 600 kPa (5 bar). Thus, the column for the removal of acetaldehyde included 10 theoretical stages and in these conditions allowed for the displacement of the system in the form of upper straps (this column for removal of acetaldehyde) 98 wt.% acetaldehyde, and these straps also contained a small amount of diethyl ether. The loss of diethyl ether in this thread has been evaluated in 9 wt.%. The product withdrawn from the base of the column for removal of acetaldehyde, consisted of 60 wt.% diethyl ether, and the rest were boiling impurities.

The composition of the materials withdrawn from this column (to remove acetaldehyde), which worked under a gauge pressure of 600 kPa (5 bar), presented below in table 8.

The temperature profile of the column for removal of acetaldehyde are presented in the following table 9.

To prevent the accumulation of noeater returning it to the reactor was selected 70,5 kg/h reset.

Column (D) of the clean water

The aqueous phase is withdrawn from the apparatus for decanting column (C), was pumped into the column (D) purification of water. This column (D) included 15 theoretical stages, and the source material was applied to a point above the 5th from the top step. Column (D) worked with a coefficient reverse flow of 0.75:1.

In column (D) of the water in the form of azeotrope as the top straps were removed ethanol and ethyl acetate, after which they were returned to the reactor as recycle ethanol). Then the material is withdrawn from the base, which consisted essentially of water, containing a total of less than 150 ppm million of organic matter returned to the apparatus for decanting associated with the column (S) or sent to the system exhaust flow. Column (D) worked under atmospheric pressure.

The composition of the material presented in the following table 10.

The temperature profile for column (D) presents the following table 11.

Column (E) for the purification of ethyl acetate

The crude ethyl acetate, taken from the base of the column (S) sent in column (E) purification of ethyl acetate, giving him 30 on the top plate of 50 plates (efficiency of the plates was evaluated as blizkimi return approximately 50% of the distillate. This column could also be run at a lower coefficient of reverse flow, if the amount of impurities present in the raw materials used in modern, was less typical. Ethylpropane, average hydrocarbon shoulder straps and heavy hydrocarbons, which were taken as the upper straps of the column (A), for example, in the form of azeotrope with water, squeezed from the base of the column (E). Column (E) worked in such a way that the total number precultivated ethyl acetate was 0.3% in terms of original material, which was entered in column (E).

Heavy hydrocarbons, which included mainly With10hydrocarbons and a number With9hydrocarbons, relatively easily separated from ethyl acetate. However, With the above8hydrocarbons interacted, apparently with ethyl acetate, resulting in their volatility was higher than expected on the basis of their boiling points. To reduce the concentration of these components to an acceptable level used high ratio of return flow and a relatively large column. The presence of olefins in the product is undesirable because even in low concentrations will adversely affect the smell of atili not in the form of upper straps, and from the base of the column (E). The composition of various materials are presented in the following table 12.

Column (E) can operate at room and elevated temperatures. Under atmospheric pressure in the case of the source material presented above, column (E) worked in the temperature profile, which is presented in the following table 13.

Column (E) is important, because the product is purified by bringing the content of impurities, such as C8hydrocarbons, below levels that are acceptable to consumers.

Possible alternatives

There are a number of possible alternative options distillation section, allowing to minimize the consumption of material resources. Thus, in particular, it concerns the work of cleaning column (E), when the amount of impurities formed in the reactor, a little. In these circumstances, the necessary separating ability of the cleaning column is relatively low. There are the following possible alternatives.

A. The reduction ratio of the reverse flow: provided that it has functionality over a wide range of parameters, column (E) is allowed a specified time.

B. Disabling columns (E) and work with a side fraction from the column (A):

This technology allows you to remove impurities in the form of secondary straps (because they are somewhat less volatile than ethyl acetate) as a side fraction near the head of the column (A). This may be desirable when a high content of impurities, because the necessary high speed of displacement, resulting in the loss of ethyl acetate can be large.

C. Disable columns (E) and the discharge of product as a side fraction from the column (C): a low impurity content of the product is of acceptable quality, you can also get the exhaust stream of an ethyl acetate product as a side fraction from the level, which is close to the base of the column. In this case, the heavier impurities are forced out from the base of the column (S).

, Disable column (E) (or reduction ratio reverse flow) and passing the product stream through the cleaning layer: This cleaning layer may include or activated charcoal, molecular sieve, or diatomaceous earth, or various macroporous resin hydrophobic or hydrophilic nature. Cleansing layers, including a highly porous materials may have the ability to catch impurities.

2. The method according to p. 1, wherein the acid catalyst used for the reaction of accession, choose from postinoculation, phosphonoacetate and heteropolyanions catalysts.

3. The method according to p. 1 or 2, wherein the catalyst supported on a carrier.

4. The method according to any of the preceding paragraphs, in which column (A) operates at a rate of reverse flow of organic material to 0.5:1, it is possible that, given the internal irrigation total factor reverse flow of organic material is 1:1 due to return to this column at least part of the organic phase and throughout the aqueous phase as phlegmy.

5. The method according to any of the preceding paragraphs, in which column (A) is either (a) using an ethyl acetate filling, or (b) in the mode water sasam ethyl acetate, ethanol and some water, is passed into the static mixer, which ensures homogeneous mixing and matching, and the homogeneous mixture is fed to the apparatus for decanting (C1), which allows you to separate an organic phase comprising ethyl acetate, the aqueous phase comprising ethanol, and where the organic phase leaving the apparatus for decanting (C1), is returned to the column (S).

7. The method according to p. 6, where the homogeneous mixture is fed into the apparatus for decanting after single or multiple washing the organic phase with water to remove ethanol.

8. The method according to any of the preceding paragraphs, in which the exhaust from the apparatus for decanting (A1) is rich in ethyl acetate phase containing all boiling impurities, including but not limited to acetaldehyde and diethyl ether, served on the 12-th from the top stage of the column (C) refining of ethyl acetate, which includes 48 theoretical stages and operates under a gauge pressure of 250 kPa (1.5 bar) and at a molar ratio of reverse flow 27,4:1, and wherein the ethanol and water are removed from this column (C) as a side fraction from the 20-th stage.

9. The method according to p. 6, in which the composition flows for columns (C) and apparatus for decanting (C1) shown below (wt.%):

11. The method according to p. 10, in which the composition of the flows of the column to remove apitalized below (wt.%):

12. The method according to p. 10 or 11, in which the temperature profile of the column to remove apitalized as follows: the temperature of the first plate is 87C, the fifth plate 97,0C, on the tenth plate of 100C.

13. The method according to any of the preceding paragraphs, in which the crude ethyl acetate, the exhaust from the base of the column (S), send in column (E) purification of ethyl acetate, operating at a mass ratio of the reverse flow of about 2:1, resulting in phlegmy return approximately 50% of the distillate.

14. The method according to any of the preceding paragraphs, where in column (A) to remove the acid is separated boiling components from the liquid comprising unreacted acid, water and heavy components, at least part of the liquid removed in the form of rejection from the base or near the base of the column (A).

15. The method according to p. 14, in which the liquid is withdrawn from the base of the column (A), PFD heavy hydrocarbons, dispersed in the acid, and then passed through a layer of ion exchange resin capable of removing dissolved or suspended released from the corrosion heavy metals.

16. The method according to p. 14 or 15, wherein the layer ion-exchange resin is a layer of cation exchange resin.

17. The method according to any of paragraphs.15 and 16, in which the liquid eluate obtained after transmission through a layer of ion exchange resin, send forth to the 2nd top plate of the evaporator, including 5 plates (with the efficiency of the plate is approximately 50%), and ethylene reagent in the basis of the same evaporator, thanks to evaporate the acid and the products recyclo.

18. The method according to p. 17, wherein using the evaporator, equipped with a liquid demisters located at the level of the upper plate, with the aim to minimize the transfer of any liquid.

19. The method according to p. 17 or 18, wherein, to prevent the possible transfer of heavy metals together with the vaporized acid and ethylene for washing vapor recycle acid when they climb the evaporator above the level of the upper plate of the evaporator injected fresh acetic acid.

20. The method according to p. 18 or 19, wherein prior to submission to the reactor for the reaction of direct connections etileno selection from a mixture of ethyl acetate, as components comprising ethanol, water and ethyl acetate, characterized in that a) provide homogeneous mixing of these components in order to ensure their coalescence and b) homogeneous mixture from stage (a) serves in an apparatus for decanting, designed to ensure separation of the ethyl acetate in the organic phase from ethanol and water in the aqueous phase by separation up until the concentration of the aqueous phase in the organic phase was less than 1000 ppm million in terms of the whole organic phase.

22. The method according to p. 21, where the step of homogeneous mixing is carried out using a static mixer.

23. The method according to p. 21 or 22, where one or more of the steps of washing the organic phase with water to carry out the directions of the mixture in the apparatus for decanting (C1)

24. The method according to p. 21, wherein the concentration of the aqueous phase in the organic phase is less than 300 ppm million in terms of the whole organic phase.

25. The method according to p. 21 or 22, wherein separating the aqueous phase from the organic phase is achieved by the use of the device for decanting, characterized by an internal design that allows you to better target separation.

26. The method according to any of the preceding paragraphs.21-23, when C. The method according to any of the preceding paragraphs.21-23, in which the separation of the aqueous phase from the organic phase reach regulation length of stay of a homogeneous mixture in the apparatus for decanting.

28. The method according to any of the preceding paragraphs.21-25, in which the separation of the aqueous phase from the organic phase is achieved using a combination of internal construction of the apparatus for decanting with a duration of stay of a homogeneous mixture.

Paragraphs 1-28 formulas have equal priority from 25.04.1998 and 07.01.1999.

 

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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
The invention relates to a technology for production of acetic acid and its derivatives by isomerization of methylformate in the presence of water, aliphatic carboxylic acid WITH1-C10as solvent and catalyst system

The invention relates to chemical technology, in particular to a method for producing sec-butyl acetate (BWA), used as a solvent for paints and varnishes and for the production of sec-butyl alcohol

The invention relates to a method for producing 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 process of extracting the ethyl acetate from the reaction mixtures
The invention relates to the field of chemistry, and more specifically, to method selection monoisobutyrate-2,2,4-trimethyl-1,3-pentanediol from condensation products of samalanga aldehyde in the presence of a catalyst is an aqueous solution of alkali

The invention relates to chemical technology, and in particular to methods of separation hardly separated commercial mixtures containing butanol, butyl acetate and impurities, e.g., biological, such as antibiotic products of inactivation, pigments, and can be used in chemical, pharmaceutical, paint and other industries

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 an improved process for the preparation of alkylacrylate with high yield and high purity

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
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