Effect of MoCl5 addition on the carbonization and the subsequent steam activation of pitch and coking coals

The present work is devoted to the study of the role of MoCl5 and its by-pr oducts on reactions involved in pore formation during the preparation of ac tivated carbon for the manufacture of carbon-supported catalysts. The carbo naceous precursors were a coal tar pitch and three bituminous coals of incr easing rank. Continuous detection of evolved tar and gas during carbonizati on was implemented and the data were correlated with the porosity developme nt during carbonization and subsequent steam activation. It was found that MoCl5 promotes the microporosity growth during carbonization by dehydrogena tion reactions leading to cross-linking and condensation reactions, The por es left in the char, as well as the residual molybdenum compounds, favour t he development of the porosity during steam activation, (C) 2000 Elsevier S cience Ltd, All rights reserved.