CO2 Gasification Reactivity and Kinetics Studies of Raw Coal, Super Clean Coal and Residual Coals obtained after Organo-refining (Solvent Extraction)

Durlubh Kumar Sharma, C.C. Giri


Gasification of coal is important for the generation of H2. This is also good for Integrated Gasification Combined Cycle
(IGCC) power generation which can be easily and relatively cheaply combined with CO2 concentration, storage and utilization
systems. Solvent extraction of coal in organic solvents results in the production of super clean coal, mostly having less than
1% ash. The present paper reports the effect of solvent extraction (organo-refining) of Samla coal by using an industrial
solvent, such as N-methyl-2-pyrrolidone (NMP), a coal derived solvent, such as, anthracene oil (AO) and a petroleum derived
solvent, i.e. cetene (CE), on the CO2 gasification of coal. Different solvents had different effects on the CO2 gasification of
super clean coal (SCC) or of residual coal (RC) obtained after the organo-refining of coals in different solvents. The CO2
gasification reactivity of raw coal as well as of solvent treated coals was found to increase with increase in the temperature of
the gasification from 900 to 1100C. The treatment of coal with solvents has been found to affect the CO2 gasification reactivity.
Super clean coals obtained from the organo-refining in the cetene and NMP showed good CO2 gasification reactivity. Residual
coals obtained from the organo-refining in NMP and CE also showed good CO2 gasification reactivity. Kinetics studies have
revealed that the activation energies of CO2 gasification reactions are reduced as a result of organo-refining of coal in different
solvents. While organo-refining of coals in NMP and if possible in CE as well may help in obviating some of the major
engineering problems in IGCC power generation, this integration may not be economically attractive at present. Future IGCC
power generation may involve the use of CO2 and O2 as the gasifying medium.


CO2 gasification, organo-refining, NMP, anthracene oil, cetene, active surface area, catalysts, mineral matter, diffusion controlled kinetics

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