CO₂ gasification of activated carbon catalyzed by earth alkaline elements

Oxy-fuel combustion: The effect of coal rank and the role of char-CO2 reaction

“…Ye [28] studied the gasification of Bowmans coal with CO 2 and steam and found the reaction to be strongly catalyzed by Na, K and Ca. The effectiveness of catalysts for the CO 2 gasification reaction by alkaline-earth elements is in the following order: Be≈ Mg b Ba≈ Sr b Ca [26]. Kapteijn et al [26] have indicated that calcium oxide (CaO) is the active species in the CO 2 gasification reaction.…”

“…The rate of the gasification reaction is enhanced by the presence of alkali and alkaline-earth metal salts or oxides [24][25][26][27][28] and their importance increases with decreasing rank of coal (Cb 80%) [25]. Ye [28] studied the gasification of Bowmans coal with CO 2 and steam and found the reaction to be strongly catalyzed by Na, K and Ca.…”

Impacts of vanadium and coke deposits on the CO2 gasification of nickel catalysts supported on activated carbon from petroleum coke

“…This value of conversion was chosen to provide a comparison to other data in the literature [17]. The activation energy of the uncatalyzed petcoke AC was 184 kJ mol −1 , which is approximately 100 kJ mol −1 lower than the values reported for the CO 2 gasification of other AC-290 kJ mol −1 (20% conversion) [17], 250 kJ mol −1 (conversion not reported) [33], and 260 kJ mol −1 (conversion not reported) [10]. With the addition of Ni, the activation energy decreased.…”

Reactivity of young chars via energetic distribution measurements. Final report, 1 September 1990--31 December 1994

“…It is generally agreed that the mechanism for steam gasification share certain similarities with that for C02 gasification. Kapteijn et al (1986) concluded that the activation energy is not affected by the presence of catdysts in C02 gasification, and suggested that the catalysts only serve to increase the number of active sites. This is consistent with the results in the preceding section.…”