STEAM GASIFICATION OF LOW-RANK COALS WITH A CHLORINE-FREE IRON CATALYST FROM FERRIC-CHLORIDE

A novel method for converting FeCl3 to an active, Cl-free Fe catalyst for coal gasification has been studied. Fe cations alone can be incorporated into low-rank coals from an aqueous solution of FeCl3 by using NH3/NH4Cl solution. Some Fe cations are exchanged with the protons in carboxyl groups. The Cl-free Fe results in a finely dispersed catalyst, which shows a high activity for gassification with steam at around 950 K. The degree of rate enhancement by the Cl-free catalyst depends on char conversion, Fe loading, and temperature. The chemical form of the Fe catalyst on devolatilization and during gasification is Fe3O4. The catalytic activity is discussed in terms of the dispersion of Fe3O4 particles.