SUCCESSIVE PULSING OF AN IRON-LOADED CANADIAN SUBBITUMINOUS COAL CHAR

Successive, alternating Pulses Of CO2 and N2 fed to beds of iron-impre gnated coal char confirm the existence of a redox cycle with iron cata lysts. Additional experiments with chars from raw and demineralized co als establish that the catalytic gasification dominates and that the c oal ash also functions through a redox cycle. Extending the duration o f the CO2 pulse leads to a plateau in the rate of CO formation that ha s not been previously observed. A redox cycle involving easily oxidize d and reduced iron oxide species is proposed as the mechanism for gasi fication in this plateau region of the pulse.