Direct versus Hydrogen-Assisted CO Dissociation

摘要

Carbon monoxide is a potential substitute for crude oil as a feedstock in the production of liquid hydrocarbons via the Fischer-Tropsch (F-T) process. This process initiates through CO dissociation, and hence, a fundamental understanding of CO activation is of utmost importance. Extensive experimental and theoretical studies have been carried out to investigate the reaction path of CO dissociation and identify the active site that would be responsible for the low CO dissociation barrier. These studies have confirmed that the active sites present along stepped and corrugated metal surfaces reduce the CO dissociation barrier. Basically, two mechanisms for CO activation have been hypothesized. One proposition suggests that chain growth in the F-T process is initiated via the carbide mechanism, which involves CO dissociation followed by hydrogenation to produce CH_x species.