Carbon dioxide gasification of various iron-loaded carbon species such as Yallourn coal char, carbon black, and activated carbon were investigated. Catalytic effect of iron was pronouncedly observed when less reactive carbons such as carbon black or activated carbon was gasified at 800 degrees C. Cyclic gasification in which a gasification agent and a product CO were fed alternately was carried out in order to enhance activities of iron catalyst. When appropriate intervals in the feeding of CO2 and CO was selected (CO2 75 s and CO 120 s), gasification rate increased considerably, even with the shorter effective gasification time. Moreover, instantaneous gasification of iron-loaded carbons occurred, if the iron-loaded carbons were treated with CO at 780 to 800 degrees C for 120 s before introducing CO2. Such phenomenon is called rapid gasification and is only observed when highly dispersed alpha-iron (elucidated by EXAFS) was produced on the carbon surface. The most significant rapid gasification was observed and about 70% of original carbon was gasified within 4 min at 800 degrees C, when 1.8 mmol of iron was loaded on 1 g of carbon black (surface area 101 m(2)/g).