Catalyst Deactivation During Direct Coal Liquefaction

摘要

A review of the research and development efforts in catalytic direct liquefaction has shown that, just as in petroleum residuals refining, catalyst lifetime is more important than initial activity. Deactivation studies indicate that contamination by 20 to 30 weight percent carbonaceous material and 2 to 8 weight percent inorganics result in deactivation best described by the shell progressive deactivation mechanism. Metals contamination is confined to the outer several hundred microns of the catalyst and pore volume distributions show a marked change towards higher average pore size in support of this mechanism. Close examination of the mechanistic behavior of catalysts in direct liquefaction indicates that their primary function is hydrogenation of solvents. (ERA citation 08:031073)