GLYCOL EXTRACTION AND PURIFICATION Russian patent published in 2012 - IPC C07C29/80 C07C31/20 B01J8/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of separating a solution of homogeneous catalyst from unrefined monoethylene glycol (MEG) and purifying MEG, for use in catalytic conversion of ethylene oxide (EO) to MEG, where the method involves the following steps: separating the catalyst solution in a catalyst separation section by evaporating unrefined MEG and feeding the unrefined MEG into a rectification section, a section for separating light fractions and from there into a pasteurisation section, where each section works at pressure lower than atmospheric pressure of 0.5×10⁵ Nm^-2 or lower, where the rectification and pasteurisation sections are at pressure lower than that of the catalyst separation section, where the method provides pressure difference between the catalyst separation section and the rectification section, and where the vapour phase of the unrefined MEG from the catalyst separation section is fed essentially as vapour-phase feed into the rectification section. The invention also relates to apparatus where said method can be realised, as well as use of said method and apparatus in a process or block for catalytic conversion of EO into MEG.

EFFECT: invention enables to reduce the process to a one-run process of evaporating a stream of monoethylene glycol, which enables to transport vapour from the catalyst separation section into the monoethylene glycol purification step without using a mechanical pump.

12 cl, 3 dwg