Elucidation of hydrodesulfurization mechanism using 35S radioisotope pulse tracer methods

Abstract

Molybdenum-based catalysts as hydrodesulfurization (HDS) catalysts are among the most important industrial catalysts. One of the new approaches characterizing the structure of such catalysts and the behavior of sulfur over the “working” catalyst is a 35S radioisotope pulse tracer method (RPTM). By tracing the behavior of sulfur in the HDS reaction and sulfur exchange reaction over the sulfided Mo Al 2O 3 and Co Mo Al 2O 3 catalysts under practical reaction conditions, it becomes possible for us to observe the catalytic behavior of the catalyst in situ. The formation process of active sites, the important role that H 2S plays in this process, and the promotion by cobalt for Mo Al 2O 3 catalyst have become better understood.