Oxychlorination-Dehydrochlorination Chemistry on Bifunctional Ceria Catalysts for Intensified Vinyl Chloride Production

摘要

Ceria catalyzes the one-step production of the vinyl chloride monomer (VCM) from ethylene with a high yield because of its bifunctional character: redox centers oxychlorinate ethylene to ethylene dichloride (EDC), which is subsequently dehydrochlorinated to VCM over strong acid sites generated insitu. Nanocrystalline CeO2 and CeO2-ZrO2 lead to a VCM yield of 25% in a single pass, outperforming the best reported systems and reaching industrially attractive levels. The use of CeO2 intensifies the current two-step process within PVC production encompassing CuCl2-catalyzed oxychlorination and thermal cracking. In addition, ceria-based materials offer stability advantages with respect to the archetypical CuCl2-based catalysts.