Vapor-Phase Propylene Epoxidation over Gold Catalysts

摘要

Gold nanoparticles deposited on anatase TiO_2 by the deposition-precipitation method can produce propylene oxide (PO) in the gas phase containing propylene, oxygen, and hydrogen at temperatures from 323 - 373K. Although the selectivity to PO is very high above 90%, there remain three serious problems in commercializing the direct gas phase process: the conversion of propylene is below 2%, hydrogen efficiency (PO/H_2O) is 10 ～ 30%, and rapid catalyst deactivation. We have attempted to solve the deactivation problem, which is mainly caused by the accumulation of oligomerized compounds of PO and its successive oxidation products.