Temperature-programmed reaction (TPR) combined with isotope labelling is used to probe the CaCO3-catalyzed CO2 gasification of carbon. The identity and reaction chemistry of the surface species are probed with secondary ion mass spectrometry (SIMS). As carbon gasification begins, most of the CaCO3 decomposes to form CaO and CO2. The CaO species, which are observed by SIMS, appear to catalyze gasification by an oxidation-reduction mechanism that is similar to the mechanisms for Na and K catalysts. The catalyst oxidation step is shown to be reversible and in equilibrium, while the catalyst reduction step is rate limiting and essentially irreversible.
All Science Journal Classification (ASJC) codes
- Materials Science(all)