MXPA00008078A - Process and apparatus for the production of butylacetate and isobutylacetate - Google Patents

Abstract

The invention relates to a process of butylacetate production by esterification of acetic acid with butanol in the presence of a solid acidic catalyst in which distillatory separation of components runs simultaneously with esterification. Thus, acetic acid and butanol are introduced in defined amounts and in the molar ratio 1:1 to 1:10 into a system, in which the reaction and the distillatory separation proceeds in three zones. The reaction together with distillatory separation of the components with different boiling points run in the reaction zone, while only distillation takes place in lower and upper separation zones. A volatile mixture is separated in the upper separation zone, from which, after being cooled at 5 to 80°C water and organic phases are separated, the latest being refluxed into the system. The ratio of thefeed amount to the organic phase reflux amount is 1:1 to 1:20, the reflux amount representing 60 to 100%of the whole amount of the organic phase. Butylacetate is separated as a high boiling bottoms product. The invention relates also to a process of isobutylacetate production by esterification of acetic acid with isobutyl alcohol in the presence of a solid acidic catalyst in which separation of components by distillation runs simultaneously with esterification.

Description

PROCESS AND APPARATUS FOR THE PRODUCTION OF BUTYL ACETATE AND ISOBUTILO ACETATE Technical Field The invention relates to a process for the synthesis of butyl acetate by esterification of acetic acid with butanol. by distillation accompanied by chemical reaction using a column in which the separation of the reaction products takes place together with the esterification in a catalytically active separation equipment. The invention also relates to a process for the synthesis of isobutyl acetate by esterification of acetic acid with isobutyl alcohol, by the method of catalytic distillation using a column in which the separation of the reaction products takes place together with the esterification in a catalytically active separation equipment. The invention also refers to apparatuses for carrying out said process.

BACKGROUND OF THE INVENTION Butyl acetate is prepared by the reaction of butanol with acetic acid, by which water is produced in addition to butyl acetate. The reaction is reversible and acid catalysts are used to accelerate it. Mineral acids, especially sulfuric acid, or more recently, ion exchange resin (EP 066059, DE 3636754), or zeolites and so-called solid superacids are also used for this purpose. According to the processes of the state of the art (Petrochemia 1985, 25, 99), almost equilibrium composition is achieved in a reactor, and the resulting mixture is then destined by means of a distillation column to separate a mixture, the composition of which is similar to the composition of the ternary azeotrope of butanol-butyl acetate-water. The amount of the water of reaction is not sufficient to distill all the butyl acetate in the aforementioned manner, therefore additional water must be added. The volume of the waste water to be subsequently treated is thus increased, which is one of the main disadvantages of the processes known in the art. The mentioned steps are very often combined, for example the synthesis takes place directly in the reheater of the distillation column. The separation of the organic phase from the heterogeneous azeotrope aqueous phase prepares the conditions for the subsequent separation of butanol butyl acetate by distillation of the organic phase in another distillation column from which a mixture containing butanol, traces of diluted water and a small amount of butyl acetate is removed as distillate. This outgoing product in the upper part is recycled while the butyl acetate of purity usually up to 98% by mass, is removed as a product in the bottom. The separation of the unreacted butanol from butyl acetate is very difficult due to the strong non-ideality of the mixture. Not only butanol, butyl acetate and water create a ternary azeotrope with minimum boiling point, but also butanol with butyl acetate as well as butanol with water create binary azeotropes. The separated aqueous phase of the distillate of the first column is subsequently distilled by the use of another distillation column, with the dissolved butanol and butyl acetate being separated as the distillate, this mixture is recycled to the process. The complex separation of the components of the esterification reaction mixture is the main disadvantage of the processes of the state of the art. There are also serious corrosion problems as an additional disadvantage in these processes, which use mineral acids as catalysts. Another variant of the synthesis of butyl acetate takes a possibility to carry out the reaction in a packed column reactor with ion exchange catalyst accommodated in two zones (CN 1107136A). There is a partial condenser placed at the head of the column. The vapors are partially condensed in the condenser, the distillate is heated to reflux towards the upper reaction zone without being divided into the aqueous and organic phases. This has an adverse impact on the balance of the reaction, which is a considerable advantage of such a system. The vapors, not condensed in the partial condenser, constituted at the head of the column, are condensed in an external condenser, the condensate being heated to reflux in the feed of the column after the separation of the water to the organic phases, so that the problem of the accumulation of low-boiling impurities in the upper part of the column remains unsolved. The product is removed from the bottom of the reactor. The maximum purity is only 95 to 98% by mass according to the patent (CN 1107136A). The isobutyl acetate prepared by the reaction of isobutyl alcohol with acetic acid, whereby water is also produced in addition to isobutyl acetate. The reaction is reversible, acid catalysts are used to accelerate it. Mineral acids are used for this purpose, especially sulfuric acid or, more recently, solid acid catalysts, as can be seen for example from CZ 191357 and CZ 279562. These catalysts can be ion exchange resins, zeolites, also called solid superacids and similar. According to the processes of the state of the art in relation to the preparation of isobutyl acetate, the composition almost in equilibrium is achieved in a reactor, the composition is dependent on the initial molar proportion of the components of the reaction. The resulting mixture is then distilled by means of a distillation column to separate a mixture, the composition of which is similar to the ternary azeotrope composition of isobutyl alcohol-isobutyl acetate-water. The amount of the water of reaction is not sufficient to distill all the isobutyl acetate in the aforementioned manner, therefore additional water must be added to the mixture. The volume of the waste water to be subsequently treated is thus increased, which is one of the major disadvantages of the process known in the art. These steps are very often combined, for example, the synthesis takes place directly in the reheater of the distillation column. After separating the organic phase from the aqueous phase of the heterogeneous azeotrope, it is possible to separate the isobutyl acetate from the isobutyl alcohol by subsequent distillation of the organic phase in another distillation column. The organic phase, separated from the heterogeneous azeotropic mixture, contains isobutyl alcohol, isobutyl acetate and a certain part of water. The isobutyl alcohol, the rest of the water and a small part of the isobutyl acetate are separated from the organic phase by subsequent distillation. The product leaving the top, obtained in this way, is recycled towards the esterification while the pure isobutyl acetate is removed as a product in the bottom. The separation of the unreacted isobutyl alcohol from isobutyl acetate is very difficult due to the strong non-ideality of the mixture. Isobutyl alcohol and isobutyl acetate create a binary azeotrope, also creating a ternary azeotrope with a minimum boiling point with water. The separated aqueous phase of the distillate of the first column is subsequently distilled by means of another distillation column, the dissolved isobutyl alcohol and the dissolved isobutyl acetate being separated in the upper part, their mixture being recycled to the process. The complex separation of the components of the esterification reaction mixture is the main disadvantage of these processes of the state of the art. There are also serious corrosion problems as an additional disadvantage in those processes that use mineral acids as catalysts.

Description of the invention Process for the production of butyl acetate The process for the production of butyl acetate by esterification of acetic acid with butanol in the presence of a solid acid catalyst consists, according to this invention, of introducing acetic acid and butanol in a molar ratio of 1: 1 to 1:10, total amount of feed per unit volume of the catalyst is 0.1 to 10 h_1, in the system of tines zones in which the reaction and distillation take place, running the reaction simultaneously with the distillatory separation of the compounds from different points of boiling in the reaction zone, while only the separation of the components by distillation takes place in the upper and lower separation zones, namely the components forming a ternary azeotrope with a minimum boiling point in the upper separation zone, the mixture of volatiles of these compounds is divided into water and organic phases after being cooled from 5 to 80 ° C, the organic phase is heated to reflux towards the upper separation zone, the proportion of the feed to the organic phase which is heated to reflux is from 1: 1 to 1:20, the reflux representing 60 to 100% of the total amount of the separated organic phase, and butyl acetate being removed as a bottom, high boiling product. According to this process, acetic acid and butanol can be introduced into the reaction zone or into the upper separation zone. Alternatively, acetic acid and butanol are introduced into the system separately, with the acetic acid being introduced into the reaction zone or into the upper separation zone, the butanol is introduced into the reaction zone or into the lower separation zone according to This process. Finally, 1 to 99% of the total amount of butanol is introduced as a mixture with acetic acid in the reaction zone or in the upper separation zone of the system, while 99 to 1% of butanol are introduced separately into the zone of reaction or in the lower separation zone at the same time, according to this process. In a preferred embodiment, the process is carried out at a molar ratio of acetic acid vs. butanol in the range of 1: 1 to 1: 1.3, the feed flow per unit volume of catalyst is 0.5 to 5 h "1, the proportion of the reflux feed flow of the organic phase is 1: 2 to 1: 7 and from 90 to 99% of the volume of complete separated organic phase, it is heated to reflux.The acetic acid or the mixture of acetic acid and butanol fed to the system may also contain butyl acetate and / or water. In this way it is possible to feed, for example, a partial conversion product of butanol-acetic acid mixture which contains at the maximum the equilibrium concentration of butyl acetate and water in addition to butanol and unreacted acetic acid. The invention can advantageously be carried out in an apparatus comprised of a column consisting of three zones, in which the reaction zone placed in the middle part of the column contains a solid and mobilized acid catalyst in the reaction zone on the distillation plates or by other systems known per se which ensure good contact between the liquid phase and the catalyst particles, as well as between the liquid and the vapor phases in the countercurrent flow of these phases, for example the catalyst can be embedded in a structural packing with internal channel structure by fixing it between two layers of an inert porous material that forms the structure of the packaging; the upper and lower separation zones contain inert structural packing, common tower packing or distillation plates, the butanol feed pipe is connected through a shut-off valve to the acetic acid feed pipe, the joint feed is introduced into the reaction zone or above this zone, a second arm of the butanol feed tube is connected to the reaction zone or below this zone is also equipped with a shut-off valve, a Reheater is connected to the bottom of the column, the butyl acetate removal line is led from the reheater or the bottom, the head of the column that ends at the top of the column is connected to the condenser by a steam pipe , the condensate line leads from the condenser to the separator towards the top of which a reflux tube and a withdrawal tube for the organic phase not refluded, are connected while the tube of the aqueous phase is connected to the bottom of the separator. In a possible arrangement, the shut-off valve and butanol feed control is closed, the shut-off valve and pipe connection control is opened, in yet another arrangement, the shut-off valve and butanol feed control is opened, the Shut-off valve and tube connection control is closed. Finally, the shut-off and control valves are open. In addition to feeding the butanol and the acetic acid independently at different points of the apparatus, the configuration of the feeding tubes described above makes it possible to feed butanol or at least part of it in a mixture with acetic acid to a point in the zone of reaction or in the upper separation zone, it being possible for additional butanol to be fed via an independent feed line to the point in the reaction zone or in the lower separation zone placed below the feed point of the butanol acetic acid. The same effect can be achieved by preparing the butanol-acetic acid mixture separately, by means of some commonly known mixing device, by feeding the mixture to the reaction zone or to the upper separation zone, with additional butanol being fed into the reaction zone or within the lower separation zone, without connecting both power lines. As can be seen from the description, the invention is based on the discovery that butyl acetate of sufficient quality can be advantageously prepared by the catalytic distillation method using a distillation column consisting of a reaction zone which it contains a solid acid catalyst of common type, while there are inert separation zones placed above and below the reaction zone. These separation zones help to establish the optimum concentration profiles of the initial compounds and the products along the distillation column. As a result, a maximum concentration of the reaction compounds in the reaction zone is achieved and, consequently, the high productivity of the equipment, the optimal use of the catalyst as well as the high quality of the product are achieved. Under the optimum conditions according to this invention, the purity of the anhydrous butyl acetate, which is removed from the superheater, is above 99% by mass.

Process for the production of isobutyl acetate: The disadvantages of the well-known processes are overcome by the process for the production of isobutyl acetate according to this invention, which consists in separately introducing acetic acid and isobutyl alcohol in a molar ratio of 1: 1 to 1:10 and in one amount, expressed as the total feed based on a unit volume of the catalyst, from 0.1 to 10 h_1, in the presence of a solid acid catalyst with simultaneous removal by distillation of the components, to a system where the reaction and separation by distillation has place in three zones, where in the reaction zone runs the reaction simultaneously with the separation by distillation of the components with different boiling points and in the two separation zones, only in the separation of the components by distillation takes place, the water formed as a byproduct of the reaction is distilled from the system in the form of a mixture aze low-boiling otrópica, after which, the distillate cools below 50 to 80 ° C, the water is separated from the organic portion of the distillate and removed from the system, while the organic components of the distillate are refluxed again , the feeds of acetic acid and isobutyl alcohol are introduced into the system in such a way that the acetic acid feed is introduced into the reaction zone or above this zone, namely at a point located higher than the input of isobutyl alcohol, and the isobutyl alcohol feed is introduced to the reaction zone or below it, the ratio between the feed amount of the reagents entering and the organic phase that is reflowed, is 1: 1 to 1 : 20 and the reflux represents 50 to 100 percent of the total amount of the separated organic phase and the isobutyl acetate that separates as a product of higher boiling point, in the ndo The ion exchange resin, for example, sulfonated styrene-divinylbenzene copolymer (1 to 25% divinylbenzene) of acidity in the range of 1 to 10 meq H + / g, can be used as the catalyst. Different types of ion exchangers, zeolites or other commonly known acid catalysts can also be used. In a preferred embodiment, the process is carried out at a molar ratio of acetic acid vs. isobutyl alcohol in the range of 1: 1 to 1: 1.5, the feed flow per unit volume of the catalyst is 0.5 to 5 h "1, the proportion of the feed flow to the refluid organic phase is 1: 2 to 1: 7 and from 80 to 99% of the volume of the separated, complete organic phase is refluxed A partially converted mixture of acetic acid and isobutyl alcohol can be fed instead of pure acetic acid, so that the feed stream The acetic acid content may also contain isobutyl acetate and / or water and / or a certain portion of unreacted isobutyl alcohol The process according to this invention is advantageously carried out in an apparatus comprised of a column consisting of three zones, the reaction zone, placed in the middle part of the column, containing a solid acid catalyst, in a preferred embodiment immobilized in well-known types of structural packing with channel structure is internal, by fixing the catalyst between two layers of an inert porous material that forms the structure of the packaging; the upper and lower separation zones contain inert structural packings, common tower packings or trays or distillation plates, the acetic acid feed pipe is introduced into the upper part of the reaction zone or above this area, while the isobutyl alcohol feed tube is connected to the bottom of the reaction zone or below this zone, the bottom of the column is equipped with a reheater, the withdrawal line of isobutyl acetate is conducted either from the reheater or from the bottom of the column, the top of the column is provided with a head equipped with a tube steam for the introduction of distilled vapors into a condenser, from which a condensate line leads to the separator, to the bottom of which a water-phase tube is connected and to the top of it a line of water is connected. reflux and a tube for the removal of the non-refluxed organic portion of the distillate.

It is apparent from the basic features of the invention described above that it is possible to achieve conversion higher than the equilibrium, practically up to 100%, of the initial compounds to isobutyl acetate according to this invention. It is the main function of the separation zones to separate the reaction products, for example, isobutyl acetate and water from the initial components, for example acetic acid and isobutyl alcohol, and return the initial components back to the reaction zone. , while isobutyl acetate is continuously separated as a bottom, high-boiling product, and the water is separated as distilled in the form of a ternary, volatile, heterogeneous azeotrope, which is removed from the system after being separated from the organic phase of the distillate, which contains mainly isobutyl alcohol and isobutyl acetate. The organic phase is completely or partially refluxed. The proportion by quantity of the initial components fed to the reflux of the organic phase is 1: 1 to 1:20, with the reflux representing 50 to 100% of the total amount of the separated organic phase.

The initial components, for example acetic acid and isobutyl alcohol can be fed either in an equimolar ratio, or some excess isobutyl alcohol can be applied to convert all the acetic acid. If the process according to this invention is run under atmospheric pressure, the following temperature profile is established: 110 to 120 ° C in the superheater and 87 to 104 ° C in the head of the column. The process according to the invention can also be carried out under reduced pressure. Isobutyl alcohol is introduced below the acetic acid inlet. Most commonly, isobutyl alcohol is introduced below the reaction zone or into its lower part, while acetic acid is introduced above said zone or at its upper part. The vapors carried from the head of the column are condensed producing a mixture that is separated in water and in organic phases after being cooled to 80-5 ° C. The total amount, or the larger part of the organic phase, is refluxed to the head of the column. The aqueous phase containing dissolved isobutyl alcohol and isobutyl acetate is removed. The dissolved alcohol and ester can be purified from the aqueous phase and returned to the process. The desired reaction product-anhydrous isobutyl acetate is removed from the reboiler at a temperature of 110 to 120 ° C. The purity of the product depends on the molar ratio and the amount of the initial components introduced into the system, and on the ratio in amount of the catalyst to the initial components, as well as on the activity of the catalyst. The product obtained is of commercial quality and it is easy to improve its quality at that level by not demanding consistent distillation.

Brief Description of the Drawings Figure 1 represents an apparatus for carrying out the process for the production of butyl acetate according to the invention. The apparatus consists of a column 1_ containing three zones, the reaction zone 2_, which contains a solid catalyst is placed in the middle part of the column 1_, while the lower separation zone 3_, as well as the upper separation zone 4_ are packaged with structural packings, common packings for tower or trays or distillation plates, the tube 5_ of acetic acid feed is connected with the tube 6_ of butanol feed by a line 9_ which is provided with a shut-off valve and control 2J__, a feed line 7_ is introduced into the reaction zone 2_ or above the upper part of this zone, while the butanol feed line 6_ is connected to a separate 8_ butanol inlet, which is provided also with a closing and control valve 2_2, which is introduced in the reaction zone 2_ or below this zone. The reboiler 1_1_ is connected to the bottom 3A of the column 1_, the butyl acetate removal line 12_ is conducted from the reheater 1_1_ or the bottom 1_0_, the head 1_3 of the column is connected to the condenser 1_5 by the steam flow line 1_4_, the condenser 1_5 being connected to the separator of phase 1_7_ by the flow line 1_6 of the condensate, the flow line _18_ of the aqueous phase is connected to the lower part, while the tube 1_9 of the reflux flow and the flow line 2_0 of the organic phase are coupled to the upper part of the separator 17. The process according to this invention is carried out by means of the apparatus described above as follows: the supply 5_ of acetic acid and the feed 6_ of butanol are either mixed together to be introduced into the zone of reaction 2_ by line 7_ of joint feeding, or can be introduced into column 1_ individually. Therefore, the butanol input line 6_ is either introduced into the acetic acid feed tube-5 or is directly introduced through the feed point 8_ into the reaction zone 2_ or, possibly, below the this zone, both routes being in this case separated by the valve 2_1_. The butyl acetate is removed via the line 1_2_ from the reheater 11, alternatively from the bottom 1_0 of the column. The distillation of vapors, containing water, part of unreacted butyl acetate and butanol, are passed from the head 1_3 of the column to the condenser 1_5_ and, finally, to the separator 11_. The aqueous phase is removed by the line] 8, the organic phase is completely or partially refluxed to the column 1_ above the upper separation zone 4_ by the line 19. A portion of the organic components can be removed.

Figure 2 shows an apparatus for carrying out the process for the production of isobutyl acetate according to the invention. The apparatus consists of a column 1_ containing three zones, the reaction zone 2 ^ containing a solid catalyst that is placed in the middle part of the column 1_, while the lower separation zone 3_ as well as the upper separation zone 4_ are packaged with structural packings, common tower packings or distillation plates, tube 5 acetic acid is connected to the upper part of the reaction zone 2_, the isobutyl alcohol feed pipe 2_6 is connected to the lower part of the reaction zone 2_, the bottom 2_7_ of the column ends at the lower part of the column 1_, the bottom 2_7 is connected to the reboiler 2__3_, to which the line 2_9 of withdrawal of isobutyl acetate is connected, the head 210 of the column ends at the top of the column, the line 211 of steam flow is connected at the head 210 of the column and the condenser 212 which is connected to the separator 214 by the flow line 213 of the condensate, the flow line 215 of the aqueous phase is connected to the lower part, while the flow line 216 of the reflux and the flow line 217 of withdrawal of the organic phase not refluid, are connected to the upper part of the separator 214. The process according to this invention is carried out by means of the apparatus described above c As follows: the 5_ supply of acetic acid is introduced into the lower part of the upper separation zone 4_ or over the upper part of the reaction zone 2_, while the 2_6 supply of isobutyl alcohol is introduced into the upper part of the reaction zone. lower separation zone 3_ or in the lower part of reaction zone 2_, the isobutyl acetate formed by the reaction is removed by line 2_9 from reheater 2_8_ or, alternatively, from bottom 27 of the column, distilling the vapors containing water, part of the isobutyl acetate and the unreacted isobutyl alcohol are passed from the head 210 of the column to the condenser 212 and, finally, to the separator 214 where the water is separated from the organic compounds, being complete or The organic phase is partially refluxed to column 1_. A certain portion of the organic phase can be removed.

Modalities for Carrying Out the Invention Example 1 The apparatus used to carry out the process according to the invention is schematically presented in Figure 1_. A distillation column 1_ operating under atmospheric pressure consisted of three zones. The reaction zone 2_ existed in the intermediate part of the column 1_, the lower separation zone 3_ was placed below, while the upper separation zone 4_ was above the reaction zone 2_. The reheater 1 \ _ was connected to the bottom 1_0, the condenser l b_ was connected to the head 1_3 of the column and to the separator 17. The reaction zone 2_ was packed with an active packing containing 33 g of acid ion exchange resin . The lower separation zone 3_ and the upper separation zone 4_ were packaged with common tower packing - Berl rollers with a characteristic dimension of 4 mm. The lengths of the separation zones 3_ and 4_ were 0.5 m. The process was carried out as follows: The 7_ supply of acetic acid was introduced above while the 8_ butanol feed was introduced below the reaction zone 2_. These initial components were fed at a rate of 0.3 mol per hour. The vapors 1_4_ were passed from the head 1_3_ of the column to the condenser 1_5. The condensed liquid was taken via 1_6 from the condenser 15 to the phase separator 1_7_. The water of reaction was removed in the amount of 5 g / h from the phase separator 1_7_ as the aqueous phase 18, while the organic phase of the destined azeotrope was refluxed via the 1_9 path to the column _1. The crude butyl acetate was removed via the __ 2_ from reheater 1_1_ at a rate that ensures constant retention in reheater 11. The conversion was 92%, the product withdrawn via line _12_ contained 90.9% by mass of butyl acetate in this regime.

Example 2 An equimolar mixture of acetic acid and butanol was injected at the rate of 40.3 g / h in the apparatus described in Example 1. 2.2 g / h of butanol was injected via line 8_ below reaction zone 2_. 5.5 g / h of organic distillate was removed by line 20_. 32 g / h of the product containing 94.5% by mass of butyl acetate were removed from reheater 11.

Example 3 The esterification of butanol with acetic acid was carried out by means of an apparatus consisting of the superheater 1_1_, the volume of which was 50 dm3 and the distillation column 1_ equipped with the condenser 3A and the phase separation 17. The column 1_ of reaction distillation consisted of the reaction zone 2_ packaged with the KATAPAK® S structural packing containing 710 g of an acid ion exchange resin in the H + form, the lower 3_ and upper separation zones 4_ were packed with the structural packing CY®, the efficiency of each zone is equivalent to 20 theoretical plates. 1.21 kg per hour of a mixture containing 43.3% by mass of acetic acid and 56.6% by mass of butanol was injected at the boundary between the reaction zone 2_ and the upper separation zone 4 through the feed line 1_. The vapors _1_4_ condensed in the condenser _1_5, the condensate 1 6_, the temperature of which was 35 ° C, was divided into water and in organic phases in the separator 1_7_. The aqueous phase was collected via 1_8_, the total volume of the organic phase was refluxed to the top of column 1_3_ track 1 _. The butyl acetate of purity of 96.01% by mass was removed via 1_2 from the reboiler 1_1_ at the speed of 1.05 kg per hour.

Example 4 The apparatus and process were the same as described in Example 3. The feed stream 7_ contained 14.16% by mass of acetic acid, 20.74% by mass of butanol, 57.32% by mass of butyl acetate and 7.8% by mass of Water. The feeding speed was 2.20 kg per hour. The mixture of this composition had been obtained by preliminary partial conversion of a mixture of acetic acid-butanol in a common type reactor packed with an ion exchange resin, acid. The butyl acetate of purity of 99.4% by mass, which contained 0.06% by mass of acetic acid and 0.25% by mass of butanol was withdrawn via _12_ from the reboiler 1_1_ at a rate of 1.91 kg per hour.

Example 5 1. 92 kg per hour of a mixture containing 15.1% by mass of acetic acid, 19.2% by mass of butanol, 55.84% by mass of butyl acetate and 9.9% by mass of water was injected through the feed line 7_ into the column described in Example 3. 0.0418 kg / h of the organic phase was collected from the distillate, by line 20. 1.62 kg per hour of butyl acetate of 99.5% purity by mass were removed from reheater 11. Not detected acetic acid by the gas chromatography method in this product.

Example 6 The apparatus was identical as in the examples 3-5. 2.80 kg / h of a mixture containing 13.16% by mass of acetic acid, 21.58% by mass of butanol, 56.52% by mass of butyl acetate and 8.72% by mass of water was injected through the feed line 1_. 0.0642 kg / h of the organic phase was collected from the distillate, by line 20_. 2.39 kg per hour of butyl acetate of purity of 99.2% by mass were removed from the heater 1_1_. Acetic acid was not detected by the gas chromatography method in this product.

Example 7 A mixture containing 17.9% by mass of butanol, 14.5% by mass of acetic acid, 58.4% by mass of butyl acetate and 9.4% by mass of water was injected through the feed line 1_ to the apparatus of the same construction as described in Examples 3-6, the feeding speed was 1.85 kg / h. At the same time, 29.6 g / h of butanol were injected via the line 8_ between the reaction zone 2_ and the lower separation zone 3_. The head pressure of the column was 600 mbar. The organic phase of the distillate was removed at the speed of 0.02 kg / h on line 2_0. 1.56 kg / h of the product containing 99.3% by mass of butyl acetate, 0.5% by mass of acetic acid and 0.2% by mass of butyl acetate were removed from the reheater 11.

Example 8 The apparatus used to carry out the production process of isobutyl acetate according to the invention is schematically presented in Figure 2_. A catalytic distillation column, operating continuously under atmospheric pressure, was divided into three zones. The reaction zone 2_ existed in the middle part of the column, the lower separation zone 3_ was placed below, while the upper separation zone 4_ was above the reaction zone 2_. The reheater 2_8_ was connected to the bottom 2_7_, the condenser 212 was connected to the head 210 of the column and to the separator 214. The reaction zone 2_ was packed with an active packing containing 33 g of an acid ion exchange resin. The lower separation zone 3_ and the upper separation zone _ were packaged with common tower packing. Berl polynes with a characteristic dimension of 4 mm. The lengths of the separation zone _3_ and 4_ were 0.5 mm. The process was carried out as follows: Isobutyl alcohol was fed via 2_6 to the lower separation zone _3, while the acetic acid was introduced into the upper separation zone 4_ track 5_. Both initial components were introduced at a rate of 0.3 moles per hour. The vapors were passed from the head 210 of the column to the condenser 212 via 211. The condensate was taken from the condenser 212 to the separator 214 via 213. The water formed by the reaction was collected at a rate of 4.9 g / h from the separator 214 as the aqueous phase 215, while the total amount of organic phase separated from the azeotrope was refluxed via 216 to the column. 33 g per hour of crude butyl acetate were removed from reheater 2_8_ through line 2_9 of isobutyl acetate. The conversion was 92% in this modality.

Example 9 The esterification of isobutyl alcohol with acetic acid was carried out by means of an apparatus consisting of a reboiler 2_8_, the volume of which was 50 dm3 and a catalytic distillation column 1 equipped with a condenser 212 and a phase separator 214. The column 1_ of reaction distillation consisted of the reaction zone 2_ packed with the KATAPAK® S structural packing containing 710 g of an acid ion exchange resin in the H + form, the lower separation zones 3 ^ and upper 4_ were packed by the structural packaging, the efficiency of each zone responded to 10 theoretical plates. The acetic acid was fed via 5_ in the amount of 0.55 kg / h to the reaction zone 2_, while 0.75 kg / h of isobutyl alcohol was injected via 25_ towards the upper edge of the lower separation zone 3_. The water formed by the reaction was collected via 215 from the separator 2L_4_, the organic phase was refluxed via 216 to the column 1 ^, a part of the organic phase (37 g / h) was removed as the distillate 217. A constant amount in the reheater 2_8_ when collecting the crude isobutyl acetate via 2_9. This product contained 0.1% by mass of acetic acid and 4.8% by mass of isobutyl alcohol.

Example 10 The apparatus and the process were the same as those described in example 2. The lower separation zone 3_ and the upper separation zone 4_ were packed with the structural packing of the efficiency equal to 20 theoretical plates. The acetic acid was injected into the system in the amount of 0.65 kg / h, the amount of the isobutyl alcohol feed was 1.02 kg / h. The amount of aqueous phase removed from the separator 214 was 0.172 kg / h, the organic phase separated in the separator 214 was refluxed to the head 210 of the column at a rate of 9.0 kg / h, while 0.43 kg / h of this phase were removed via 217. The isobutyl acetate purity of 99% by mass was removed from reheater 2_8_ in the amount of 1.07 kg / h.

Example 11 The equipment of the column was the same as that described in examples 9 and 10. The difference was that the efficiency of the lower separation zone was equal to 15 theoretical plates, while that of the upper separation zone 4 was 25 theoretical dishes. Both initial components were fed to the system at the same speed as in Example 10. The isobutyl acetate purity of 98.9% by mass was removed from reheater 28_ in the amount of 1072 kg / h.

Possibility of Industrial Application The invention can be used in the chemical industry. The product is usable as a solvent mainly in the manufacture of paints and coatings as well as an extraction solvent in the pharmaceutical industry, in biotechnology and other branches of industry.

Claims (24)

1. Process for the production of butyl acetate by esterification of acetic acid with butanol in the presence of a solid acid catalyst, accompanied by separation by distillation of the components involved, characterized by the process because acetic acid and butanol are introduced in the molar ratio of 1: 1 to 1:10, the total amount of feed per unit volume of the catalyst is 0.1 to 10 h "1, in a system in which the reaction and separation by distillation take place in three zones, running the reaction simultaneously with the separation by distillation of the compounds of different boiling points in the reaction zone, while the separation of the components by distillation takes place in the upper and lower separation zones, namely a volatile fraction is separated in the zone of separation. Superior separation, which, after being cooled to 5 to 80 ° C, is divided into aqueous and organic phases, being fluid the organic phase towards the reaction, the proportion of the feed to the refluid organic phase is from 1: 1 to 1:20, with the reflux representing 60 to 100% of the total amount of the separated organic phase and the acetate being withdrawn from the organic phase. butyl as a bottom product, high boiling point.

2. The process according to claim 1, characterized in that acetic acid and butanol are introduced into the system, as a mixture.

3. The process according to claim 1, characterized in that acetic acid and butanol are introduced into the system separately, with the acetic acid being introduced into the reaction zone or into the upper separation zone, butanol is introduced into the reaction zone or in the lower separation zone of the system.

4. The process according to claim 1, characterized in that it is introduced 1 to 99% butanol in the reaction zone and in the upper separation zone as a mixture with acetic acid, while 99 to 1% of initial butanol is introduced separately into the reaction zone or in the separation zone below Same time.

5. The process according to claims 1 and 2 or 3 or 4, characterized in that acetic acid and butanol are introduced into the system in a molar ratio of 1: 1 to 1: 1.3.

6. The process according to claims 1 to 5, characterized in that the total feed rate of the initial compounds per one unit volume of catalyst is in the range of 0.5 to 5 h "1.

7. The process according to claims 1 to 6, characterized in that the ratio of the feed amount to the reflux amount of organic phase is in the range of 1: 2 to 1: 7.

8. The process according to claims 1 to 7, characterized in that the reflux amount represents 90 to 99% of the complete amount of the organic phase separated from the distillate.

9. The process according to claims 1 to 8, characterized in that the acetic acid or the mixture of acetic acid with butanol introduced into the system also contains butyl acetate and / or water.

10. An apparatus for carrying out the process according to claims 1 to 9, characterized in that it consists of a column containing three zones, wherein the reaction zone placed in the middle of the column contains a solid catalyst, the lower separation zone and the upper separation zone contains inert structural packings, common tower packing or distillation trays, the butanol feed pipe is connected to the acetic acid feed pipe, by means of the pipe connection, provided with the shut-off valve and control in the pipe connection, a feed line is introduced into the reaction zone or over this zone, while the butanol feed line is provided with a separate inlet with the stop valve and butanol input control, the lower part of the column ends with a bottom, provided with a reheater, the butyl acetate removal line is led from the reheater or the bottom, the head of the column that ends at the top of the column is connected to the condenser by a steam pipe, the condensate line leads from the condenser to the separator from the bottom of which the water phase pipe is driven, and from the top of which a reflux pipe and a pipe of water are conducted. withdrawal for the non-refluid organic phase.

11. The apparatus according to claim 10, characterized in that the butanol closing and control valve is closed, the closing valve controlling the pipe connection is opened.

12. The apparatus according to claim 10, characterized in that the butanol closing and control valve is opened, the shut-off and control valve of the pipe connection is closed.

13. The apparatus according to claim 10, characterized in that the butanol closing and control valve is opened, the shut-off and control valve of the pipe connection is also opened.

14. The apparatus according to claims 10 to 13, characterized by fixing the solid acid catalyst in the reaction zone on the distillation trays.

15. The apparatus according to claims 10 to 13, characterized by fixing the catalyst in the reaction zone by means of structures known per se, ensuring good contact between the liquid phase and the catalyst particles, as well as the contact between the liquid and gaseous phases in the countercurrent flow.

16. A process for the production of isobutyl acetate by esterification of acetic acid and isobutyl alcohol in the presence of solid acid catalyst and the simultaneous separation of the components by distillation, characterized in that the acetic acid and isobutyl alcohol are individually introduced in a molar proportion of 1: 1 to 1:10 and in an amount, expressed as the total feed based on a unit volume of the catalyst, from 0.1 to 10 h "1, within a system in which the reaction and separation by distillation have place in three zones, where the reaction runs simultaneously with the separation by distillation of the components with different boiling points in the reaction zone, and the separation of the components by distillation takes place in the two separation zones, the water, formed as a by-product of the reaction and which forms a low-boiling azeotropic mixture with the alc Isobutyl alcohol and isobutyl acetate are distilled from the system, after which the distillate is cooled down to 5 to 80 ° C, the water is separated from the organic portion of the distillate and removed from the system, while the organic components of the The distillates are refluxed again, the feeds of acetic acid and isobutyl alcohol are introduced into the system in such a way that the acetic acid feed is introduced into the internal part of the reaction zone and above this zone, namely at a certain point. located higher than the entry of isobutyl alcohol, and the isobutyl alcohol feed is introduced into the reaction zone or below it, the ratio between the feed of the reagents that enter and the refluid organic phase is 1: 1 to 1:20 and reflux represents 50 to 100 percent of the total amount of the separated organic phase and isobutyl acetate that is separated as a bottom product, from high boiling point.

17. The process according to claim 16, characterized in that acetic acid and isobutyl alcohol are introduced in a molar ratio of 1: 1 to 1: 1.5.

18. The process according to claim 16 or 17, characterized in that the speed of complete feeding of the initial components by a volume unit of the catalyst is in the range of 0.5 to 5 h "1.

19. The process according to claims 16 to 18, characterized in that the proportion of the feed amount to the reflux amount of the organic phase is in the range of 1: 2 to 1: 7.

20. The process according to claims 16 to 19, characterized in that the reflux amount representing 80 to 99% of the total amount of the organic phase is separated from the distillate.

21. The process according to claims 16 to 20, characterized in that the acetic acid introduced into the system also contains isobutyl acetate and / or water and / or isobutyl alcohol.

22. An apparatus for carrying out the process according to claims 16 to 21, characterized in that it consists of a column containing three zones, the reaction zone containing a solid catalyst is placed in the middle part of the column, while the zone of Lower separation as well as the upper separation zone are packaged with structural packings, common tower packing or distillation trays, the acetic acid feeding tube is connected to the upper part of the reaction zone or above this area, the Isobutyl alcohol feed line is connected to the bottom of the reaction zone or below this zone, the bottom of the column ends at the bottom of the column, the bottom is connected to a reheater, the withdrawal line of isobutyl acetate is connected either to the reheater or to the bottom, the head of the column ends at the top of the column, the steam flow line is connected to the head of the column and to a condenser, which is connected to a separator by the condensate flow line, the flow line of the aqueous phase is connected to the bottom , while the reflux flow line and the withdrawal flow line of the unrefined organic phase are connected to the upper part of the separator.

23. The apparatus according to claim 22, characterized in that the solid acid catalyst is fixed in the reaction zone on the distillation trays.

24. The apparatus according to claim 22, characterized in that the solid acid catalyst is fixed in the reaction zone by systems known per se in a structure that ensures contact between the liquid phase and the catalyst particles, as well as between the liquid phases and steam in the countercurrent movement of these phases. SUMMARY OF THE INVENTION The invention relates to a process for the production of butyl acetate by esterification of acetic acid with butanol in the presence of a solid acid catalyst in which the distillation separation of the components runs simultaneously with the esterification. Thus, acetic acid and butanol are introduced in defined amounts and in the molar ratio of 1: 1 to 1:10 in a system-, in which the reaction and the distillation separation proceeds in three zones. The reaction together with the distillation separation of the components with different boiling points runs in the reaction zone, whereas only the distillation takes place in the lower and upper separation zones. A volatile mixture is separated in the upper separation zone, from which, after being cooled to 5 to 80 ° C the aqueous and organic phases are separated, the latter being refluxed into the system. The ratio of the feed amount to the reflux amount of the organic phase is from 1: 1 to 1:20, the reflux amount represents 60 to 100% of the total amount of the organic phase. The butyl acetate is separated as a high-boiling bottom product. The invention also relates to a process for the production of isobutyl acetate by esterification of acetic acid with isobutyl alcohol in the presence of a solid acid catalyst in which the separation of the components by distillation runs simultaneously with the esterification.