RU2004533C1 - Method of esters synthesis - Google Patents

Description

in the manner shown will show “l with chroma, grc5 (glo, indicated above.

The technical task was to rationally use the distilled excess alcohol and improve the quality of the target product for the color index.

This problem was solved in that in a method involving the esterification of Sic-Cie dicarboxylic acids or their anhydrides with Cs-Ci2 aliphatic alcohols with an excess of alcohol under heating and a pressure from atmospheric to residual 2.7 kPa with azeotropic distillation of reaction water vapor and alcohol through a distillation column with condensation, separating the condensate into alcohol and water, and returning the alcohol to irrigation of the column with an easy purification of the crude ether in a known manner, including distillation of the selected alcohol, in addition to distillation irrigation of this column serves excess alcohol from the stage of distillation of excess alcohol in an amount of 0.5-1.5 mol per 1 mol of acid, maintaining in the upper part of the column a temperature of not 5-20 ° C higher than the boiling point of the azeotrope alcohol: water at the current pressure value .

This self-identification, in accordance with the malicious method, has leaked, Ec in the presence of a catalyst of isotopic i. amphoteric (tetraOuy: cc1 11 1tai} 1a1h and in the absence of a catalyst at a temperature of 80-2BO ° C and atmospheric fuo pressure oi residual 2.7 kPa, depending on the ier / boiling point of a similar alcohol, or the absence of a catalyst. Temperature and the residual pressure can be kept constant and variable.

The differences of the proposed method CT known are:

additional input of excess alcohol from the processing stage of crude ether cha irrigation of the distillation column in an amount of 0.5-1.5 mol per 1 mol of brush

the temperature in the upper suit of the column is 5–20 ° C higher than the boiling point of the gas station.

In the known methods, the excess alcohol from the purification stage of the crude ether BL-O- is fed directly to the ester reactor, which degrades the color from operation to operation, and the circulating alcohol that is distilled from the QO reactor during synthesis is returned to the reflux column, after separation from it reaction water in a Florentine vessel

Maintaining the temperature in the upper part of the column 5-20 ° C higher than the boiling temperature of the azeotrope provides along with

by effective drying of the circulating alcohol, the distillation treatment of an additionally introduced recycled alcohol (excess alcohol), necessary to improve the color of the target product. An increase in the temperature in the upper part of the column by more than 20 ° С above the boiling point of the azeotrope makes refining alcohol ineffective due to violation of the column operating mode, while maintaining the temperature less than 5 ° С above the boiling point of the azeotrope does not provide an effect of improving color gi of the target product.

The claimed differences provide a tan. tsvg-bear the target product 20-69% lower than according to the well-known technologists;; i-i while maintaining the remaining quality indicators; / and, on the other hand, solve the problem of sweaty and rational use of the excess alcohol.

Thus, the proposed technical solution has novelty, because not ONhcai-iO patent and scientific literature, and inventive level, because -Bn m way does not follow from the level of tech1.

Po m „r t (periodic). I set CE-KJ for 1; the cube apparatus contains 1 tm of about 1s ml with an enamel, coils for 14 thunderstorms and a bucket for cooling,) another rectification column hangs up Zli with a diameter of 0.4 m, fluorentium-CKh vessel and sbopic of water, they will think of di- (2- t) (DOP) by the interaction of low-acid anhydride (FA, GOST 7119-77 with and:;. 1. N 1) and 2-ethylhexenol (EG, GOST) in the presence of tetrabutoxytite - -, a (TBT, T / 6-09-2738-75) as a catalyst ..

22.3 kmol FA, g kmopay Eg m 4 gTBF are loaded into the apparatus. The process is carried out at a temperature of 1 ° C and a pressure of atmos- (10.3 kPa) to a residual 30 kPa.

I ar of psda v alcohol from the esterizer through a distillation column on the right - Yu1 P; olodilymk, from where the condensate drains from the Zoo-Floentian vessel and is separated into alcohol by water. Water is drunk in a water tank, s alcohol is returned to the distillation column for irrigation. After 1 h after reaching the temperature regime, excess alcohol is fed to the distillation column for irrigation with the previous operation at a current speed so that the temperature c. ZSTM colony1 was 10 ° C higher than the temperature of the foam of the azeotropic mixture of alcohol (see table).

Synthesis of zeersch. 3b with acid chispe of crude ether O 3 mgKOH / g.

The raw ether is purified in a known manner, namely, excess alcohol is distilled off with hot superheated steam at a temperature of 165 ° C and a pressure of 20 kPa, then 500 l of a 4% aqueous solution of soda ash are treated at a temperature of 80 ° C and then at a temperature of 120 ° C and pressure 13 kPa water is distilled off, treated with sorbents - activated carbon and clay (50 kg each) and filtered. For comparison, a similar prototype synthesis was carried out. It was carried out under the same ratios of components and modes, with the difference that the excess alcohol from the purification step was loaded into a zefirizer before synthesis began.

Technological parameters and the color of the ether are shown in the table.

Examples 2-5. Esters are prepared according to the invention as described in Example 1, but with other starting reagents, their ratios and the values of the process parameters shown in the table.

For comparison, similar esters were simultaneously obtained according to the prior art method, i.e. without additional input of excess alcohol to the distillation column and at the boiling point of the azeotrope, alcohol: water.

Conditions and properties are given in the table.

When m r 6 (continuous process). On a continuous installation including a cascade of three cubic apparatus with a capacity of 2 l with an agitator, each jacket for heating, a packed distillation column 1 m high and 0.08 m in diameter, a refrigerator, a Florentine vessel and a water collector, we obtained di- (2-ethyl hexyl) phthal (by reacting phthalic anhydride and 2-ethylhexanol in the presence of sulfuric acid as a catalyst.

In the first apparatus of the cascade, melt of phalic anhydride and 2-ethylhexanol are continuously fed at a rate of 2.6 and 4.2 g-mol / h, respectively, sulfuric kielogue is introduced here at a rate of 0.04 g-mol / h. From the first cascade apparatus, the reaction mixture is continuously supplied from a constant level to the second cascade apparatus, h from the second to the third. The temperature in the first, second and third devices is 80, 100 and 120 ° C, respectively, the pressure in all devices is 2.7 kPa. Vapors of reaction water and 2-ethylhexanol boiling off during the reaction enter the refrigerator, from where the cooled condensate is sent to a Florentine vessel. From Florentine

the vessel through the bottom drain is continuously discharged to the water receiver, and the alcohol from the upper level is continuously fed to the distillation column. Also, excess 2-ethylhexanol is continuously fed to the column irrigation from the stage of distilling off the excess alcohol at a rate of 1.8 g mol / h. From the bottom of the column, alcohol enters the first apparatus of the cascade.

Raw ether with an acid number of 3.5 mg KOH / g is continuously removed from the third, last apparatus of the cascade and its color is determined.

The crude ester is purified in the usual manner adopted for the acid catalyst process, namely, it is sent for neutralization to a bottoms flow apparatus with a 2 liter stirrer, into which a 2% alkali solution is introduced at a rate of 320 g / h. The temperature in the converter is 70 ° C, the pressure is atmospheric. Then, the crude ether with an acid number of 0.07 mg KOH / g by gravity is fed from a constant level to a sedimentation tank with a capacity of 3 l, where

separated from the water-salt (lower) layer and gravity fed for washing into a 3 L apparatus, where washing water is continuously introduced at a rate of 1000 g / h. The temperature during washing is 70 ° C,

atmospheric pressure. Then, in a 3-liter sump, the raw ether is separated from the wash water, and then it is sent to a distillation distillation apparatus with a stirrer to distill off excess alcohol, in the lower part of which there is a perforated coil for supplying sharp superheated water-vapor (t steam - 170 -180 ° C, feed rate 400 g / h). The temperature in the distant apparatus is 160 ° C, the pressure is 17 kPa. Further

treatment is carried out with sorbents - coal and clay at a temperature of 80 ° C and a pressure of 4 kPa (sorbent consumption - 0.5% by weight of ether) and filtered.

For comparison, a similar synthesis was carried out according to the prototype method. It was carried out with the difference that the excess EG was not fed to the distillation column, but mixed with fresh

alcohol before serving in the first apparatus.-cascade.

(56) U.S. Patent No. 4,007,218, cl. C 07 C 69/44, 69/50, 1977.5 Patent of Germany No. 1593712,

class C 07 C 69/80, 1970.

England patent No. 1134975, cl. C 2 C, 1966.

US patent No. 3476796. cl. C 07 C 67/02, 69/80, 1965.

1 aggl-Aigl.-1 No. I08G132 to /. C 97; 69 / eG, z367.

Horsley L. Tables of azeotropic mixtures, Per. from English - M .. Publisher. foreign literature, 1951, p. 292.

Status of production of plasticizers in the USSR and abroad. - Reviews on individual productions. Chem. prom.: / L.M. Bolotina, I.K. Rubtsova and others. M .: NIITEKHIM. 1973, no. 27, p. 32-41.

A comparative table of the proposed method with the known

dp of the hepatic spray process, primedene feed a mol / hr (example 6} Test procedure, acid number is determined according to GOST 8724; 8 ° C according to the standard test procedure, according to GOST / S728 88

P-h tagging temperature (pr 4 E) and damping (pr) are variable

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Claims (1)

The claims A METHOD FOR PRODUCING COMPLEX by subsequent purification of the crude ether, including ETHERS, including esterification of the game, distillation of excess alcohol, distinguished Ce - Cie carboxylic acids or their anhydrides 5 by the fact that the distillation column is supplemented with aliphatic alcohols Cs - Cu during distillation column excess alcohol during heating and for a long time feed excess alcohol at the stages from atmospheric to residual 2.7 purification of the crude ether in the amount of 0.5–1.5 kPa with azeotropic distillation of vapors of the reaction mol per 1 mol of acid, supporting water and alcohol through rectif katsi-10 column top temperature at 5 - onnuyu column, condensing the vapor, 2 ° C above the boiling temperature, separating the condensate into alcohol and water and an azeotrope alcohol: water at 1-flowable values Alcohol .To go back to the column with pressure irrigation SRI.