Experimental and Theoretical Studies on the Influence of Carrier Gas for COS Catalytic Hydrolysis over MgAlCe Composite Oxides

Abstract

Catalytic hydrolysis of carbonyl sulfide (COS) over metal frameworks derived MgAlCe composite oxides catalyst is investigated under N 2 and CO atmosphere. A combination of experimental and theoretical methods, including in situ IR, X-ray photoelectron spectroscopy, and density functional theory calculations, is used to explain the difference of catalytic activity. Research results indicate that M-OH groups play the most important role in COS hydrolysis, but the distribution of the M-OH groups is affected by CO. There is no competitive adsorption effect between N 2 and COS on the surface of catalyst but CO and COS. Meanwhile, the hydrolysis reaction of COS is an instantaneous reaction and a noninstantaneous reaction under N 2 and CO atmosphere, respectively. In general, under N 2 atmosphere, COS is directly adsorbed on the surface of the catalyst and most of the -OH groups are adsorbed as M-OH formation. Under CO atmosphere, most of the active sites occur as CO due to the competitive adsorption effect.