SELECTIVE CATALYST FOR THE SYNTHESIS OF ETHYLENE OXIDE

Abstract

The work presents the results of research on silver catalysts for the process of selective oxidation of ethylene to ethylene oxide, obtained by impregnating a ring porous carrier with a solution of the silver amine complex. The influence of magnesium borate and calcium carbonate, introduced in promoting amounts, on the activity, selectivity, and distribution of silver in the porous structure of the carrier was studied. It has been shown that the addition of 0.002-0.0022% magnesium borate contributes to the formation of a stable colloidal solution, a reduction in the size of silver crystallites, and an improvement in their fixation in pores, which increases the active surface area of the metal and the stability of the catalytic layer. Additional administration of 0.001% calcium carbonate has a positive effect on structure formation and increases the selectivity of ethylene oxide formation. Laboratory tests at 20 atm, 220 °C, and a volumetric rate of 4000 h−1 showed that modified catalysts exhibit higher activity and selectivity indicators compared to industrial samples. The optimal silver content was determined - 10-13 wt. %, which ensures the stability of the structure and the long service life of the catalyst.