Deactivation of a hydrotreating catalyst in a bench-scale continuous stirred tank reactor at different operating conditions

摘要

Initial and midterm deactivation of a hydrotreating catalyst tested at different severity on a bench-scale continuous stirred tank reactor is analyzed. By varying temperature and space velocity during the hydrotreating of an atmospheric residue, contribution to catalyst deactivation phenomena by thermal and catalytic reactions is measured. The level of catalyst deactivation is linked to aging provoked by both coke and metal accumulation. The deposited amounts of coke and metal on the catalyst increase by rising temperature while an increment in space velocity produces higher metal accumulation but lower coke buildup. Process conditions affect the type of coke accumulated on the catalyst after the reaction, at high severity the proportion of refractory coke and the aromaticity were enhanced. The remaining activity in the spent catalyst samples tested in the hydrodesulfurization of thiophene coincides with the aging provoked by both coke and metal accumulation.