SU480695A2 - The method of joint production of glycidol and olefinic hydrocarbons - Google Patents

Description

one

This invention relates to a process for the production of glycidol, an important intermediate for the production of glycerin, and olefinic hydrocarbons.

A known method of producing glycidol and olefins in the presence of molybdenum-based catalysts by epoxidizing allyl alcohol with organic hydroperoxides. It is difficult to isolate glycidol from dilute solutions, the catalyst consumption is high, costs for solvent regeneration are significant, and glycidol is lost during isolation.

For the purpose of new glycindol yield and simplification of the technology, it has been proposed to carry out epoxidation in a solvent environment of alkanes and, after carrying out the reaction, cool the product mixture to a temperature from +10 to -50 ° C. When this occurs, the separation of the mixture into two layers. The upper layer consists mainly of solvent and contains up to 30% of the catalyst; it is returned to the enoxidized stage at the beginning of the process without regeneration. Glincidol is concentrated in the lower layer, which is further separated by a known method, for example, by distillation under vacuum.

Example 1. In the stainless steel reactor load the initial mixture containing (g) 4U, 5 allyl alcohol, 43 isopropyl benzene hydroperoxide (GPILB) and 75.4 n-hexane. The catalyst enoxidized - vanadium oxychloride - is served in the form of a solution in allyl alcohol in the amount of N0 mol / mol HP. Epoxidation of allyl alcohol is carried out at a temperature of 110 ° C, a pressure of 2 at. After 2.5 hours, the conversion of hydroperoxide reaches 95.5%, allyl alcohol - 30%, the yield of glycidol per converted HP is 92.5 mol. % i converted allyl alcohol - 99,0 mol. % The resulting reaction mixture is cooled to -16 ° C; whereby the upper hydrocarbon layer is formed and the lower alcohol layer is formed in approximately equal weight ratios.

The upper hydrocarbon layer is then used as a solvent, the lower layer is directed to separation by distillation.

Below are the composition of the layers (wt.%):

on the reacted allyl alcohol - 95.5 mol. %

The reaction mixture is cooled to -50 ° C and subjected to delamination.

The composition of the layers (wt.%):

Example 2. In the reactor load 154 g of allyl alcohol, 250 g of hydroperoxide isopropylbenzene, vanadium chloroxide in allyl alcohol, mol / mol HP. A hexane layer of the composition corresponding to Example 1 is used as a solvent. The amount of solvent is loaded to calculate the total coititration of the HP to be about 27 wt. %

At a temperature of 110 ° C for 2 h, the conversion of hydroperoxide reaches 96.4%, allyl alcohol - 56.3%. The yield of glycidol per converted hydroperoxide is 92.2 mol. %, and the converted allyl alcohol - 98,0 mol. %

Delamination of the reaction mixture at a temperature of - 16 ° C leads to the formation of two liquid phases, the composition is close to that shown in example 1.

Example 3. The allyl alcohol is oxidized as in Example 1, but c-pentane is used as the solvent. The separation of the reaction mixture is carried out at a temperature of + 10 ° C. In this case, liquid phases with a weight ratio of the layer to the upper 1.37 are formed.

Below are the composition of the layers (wt.%):

Example 4. 160 g of allyl alcohol, 180 g of tertiary butyl hydroperoxide, 3-10 mol of vanadium oxychloride per 1 mol of HP and 556 g of n-geitan are charged to the reactor. Epoxidation of allyl alcohol is carried out at a temperature of 80 ° C, a pressure of 1 atm for 2.5 hours. During this time, the co-peper of hydroperoxide reaches 97.4%, and of allyl alcohol, 70.5%. The yield of glycidol per reacted hydroperoxide is 95.9 mol. %

As in the previous examples, the heptane layer is completely or partially recovered in the process of enoxidation without regeneration.

Example 5. In a steel reactor load 649 g of allyl alcohol, 353. g of tertiary butyl hydroperoxide, vanadium chloroxide 3-10% mol / mol HP. The solvent used is a hexane layer containing (g) 1014 hexane, 28 glycidol, 234 trimethyl carbinol, and 30 methanol and acetone (products of thermal catalytic decomposition of hydronerexis).

Epoxidation of allyl alcohol is carried out at a temperature of 140 ° C and a pressure of 5 at. Under these conditions, the conversion of hydroperoxide is 99%, of allyl alcohol, 31.2%. The output of glycidol on converted hydroperoxide 87.5 mol. %, converted allyl alcohol - 93.0 mol. % (excluding glycidol introduced into the reactor).

The separation of the reaction mixture is carried out at -20 ° C.

Below are the composition of the layers (wt.%).

Upper

Lower

10.4

25.0

0.3 0.3 1.0

36.0

13.7 27.0

2.6 25.1

55.5

853 g

Total. . .

1440 g

Example 6. Allyl alcohol 106 ml / h (89 g / h) is continuously supplied to a flow type reactor along with a VOC catalyst in an amount of 0.425 g / h. Isopronyl benzene hydroperoxide is fed in another amount in the amount of 160 ml / h (165 g / h) and 530 ml / h (375 g / h) of Beisin BR-2 solvent. The temperature in the reactor is maintained at 110 ° C, the reaction time is 90 minutes. In the first hours of operation, while pure BR-2 solvent is supplied to the reactor, the process indicators are as follows: conversion of hydroperoxide to 95%, conversion of allyl alcohol to 56.6%, yield of glycidol to loaded hydroperoxide 74.3 mol. %, on the reacted hydroperoxide - 77.7 mol. %, the yield of glycidol and unreacted allyl alcohol 88 mol. % After the return solvent is supplied to the reactor and after a sufficient number of cycles of its use, a steady state occurs, which is characterized by the following, under the same reaction conditions, and at a settling temperature of -10 ± 2 ° C. The composition of the layers (wt.%):

The weight ratio of the upper layer to the lower 1.03.

Process indicators: hydroperoxide conversion 95.3%, allyl alcohol conversion 55.3%, hydroperoxide selectivity 87.7 mol. %, for allyl alcohol - 92.4 mol. %

Subject invention

The method of joint production of glycidol and olefinic hydrocarbons according to ed. St. 360336, excluding the fact that, in order to increase the yield of glycidol, simplify the technology and reduce the consumption of the catalyst, the process is carried out in alkanes and the reaction mixture after the end of the reaction is cooled to a temperature from +10 to - 50 ° C, the upper layer is returned to the beginning of the process, and glycidol is isolated from the lower layer in a known manner.