A BASIC STUDY OF CATALYST AGING IN THE H-COAL PROCESS

Samples of CoMo/Al//2O//3 catalysts used in an H-coal process demonstration run were studied to determine causes of catalyst deactivation. Physical and surface properties of the aged and regenerated catalysts were examined. Model compounds were used to assess four catalyst activity functions, viz. , hydrodesulfurization (HDS), hydrogenation, cracking and hydrodeoxygenation (HDO). Other tests were performed to study the effects of coke and metals separately on the four catalyst activity functions. Catalyst coke content and metals deposits first increased rapidly, then more gradually with exposure time in the process run. Surface area and pore volume markedly decreased with exposure time. Catalyst activities of aged catalysts showed a rapid decline with exposure time.