PNNL

Abstract

Nickel-based catalysts have been widely tested in decomposing tar and methane in hot biomass syngas cleanup researches. However these catalysts can be easily deactivated by the sulfur compounds in syngas due to the strong sulfur adsorption effect on the Ni surface. Here we report on a new regeneration process, which can effectively and efficiently regenerate the sulfur-poisoned Ni reforming catalysts. This process consists of four sequential treatments: 1) controlled oxidation at 750oC in 1% O2, 2) decomposition at 900oC in Ar, 3) reduction at 900oC in 2% H2, and 4) reaction at 900oC under reforming condition. The duration of this 4-step regeneration process is only about 8 hours, which is shorter than that of the conventional steaming regeneration treatment.