Method and apparatus for separating and purifying ethyl vanillin by decompression and continuous distillation in dividing wall column

Abstract

The invention relates to a method and device for separating and purifying vanillin by comparting wall tower to reduce pressure and continuous distillation. A vertical wall which is arranged in the middle and lower part of a distillation tower divides the tower into four areas, which are area one, area two, area three and area four. The coarse ethyl vanillin waiting to be separated, is put in from the middle and upper part of the area two which mainly finishes the separation of ethyl vanillin from the heavy components; the area three is the area in which ethyl vanillin is separated from light components, and the pure components ethyl vanillin is obtained from the lateral line in the middle and lower part of the area three; the area one is the public distillation section of the area two and the area three, and the light components is obtained from the top of the area one; the area four is the public distillation section of the area two and the area three, and the heavy components is obtained from the bottom of the area four. The single column continuous distillation of coarse ethyl vanillin is realized and high-purity ethyl vanillin is obtained from the lateral line. The invention overcomes the disadvantages of the high demand for equipment in the molecular distillation, and high energy consumption and low yield in the double tower pressure reduction continuous distillation method, and has the advantages of 'low invest, low energy consumption, high yield and high purity', large spreading and applying value and high social and economical benefits.

Description

Technical field [0001] The invention relates to a method for rectifying, separating and purifying heat-sensitive substances, in particular to a method for separating and purifying ethyl vanillin under reduced pressure and continuous distillation in a dividing wall tower, which can realize continuous separation of target products in a single tower. Background technique [0002] Ethyl vanillin is a heat-sensitive substance. It is easy to polymerize when exposed to heat for a long time, which affects product quality and yield. The rectification yield generally does not exceed 90%. This is a common problem encountered in the separation and purification of high-boiling heat-sensitive materials. In order to solve this problem, it was proposed to use molecular distillation to separate ethyl vanillin (Chemical Engineering, Vol. 35, No. 10, Qian Shenghua, etc.), which increased the yield to about 93%-95%. Although this method improves the yield, it requires a very high degree of vacuum (4...

AI Technical Summary

Problems solved by technology

Separation and purification of ethyl vanillin by continuous distillation under reduced pressure in a dividing wall column has not been reported at home and abroad so far

Images