| The method of direct hydration from ethylene oxide (EO) is the main route to the synthesis of ethylene glycol (EG) today, in which a higher water/EO mole ratio (ratio) is adopted. In order to promote the product yielding of the EG, the higher water/EO ratio lead to the fact that about 85% water in the processing products must be separated using massive energy, which have following the disadvantages, such as long processes, large equipments and enormous energy and thus affected the cost of producing EG. The studies of catalytic hydration can promote the high conversion and selectivity, therefore become the focus of present researchers.This paper is based on the results of former researchers about EG, and the process of EG of catalytic hydration has been studied with solvent. At first, the solvent glycerol has been selected, with which the solubility is compared with the original solvent EG. Then the orthogonal experiments were used to analyze the relations among the water/EO ratio, the content of catalyst and the content of solvent, which is used to find out the main effects affecting the selectivity of EG. On this basis, the process of EG of catalytic hydration has been detailed studied at the low water/EO ratio among 1.0~4.0:1. The water/EO ratio, the content of catalyst and the content of solvent's effects at lower water/EO ratio have also been discussed, and the optimization conditions have been obtained. At last, compared with the industrialized direct hydration process, the industrial popularizing hydration process which is supported by America Shell (shell-ωprocess), the hydration process without glycerol, the hydration process with glycerol have been investigated the energy cost and catalytic effects.The study in this paper have showed that the glycerol replacing EG as the carrier in the catalytic hydration process have its own advantages, which could reduce the circulation amount of solvent, cut down the energy consumption, and guarantee the...
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