Effect of Preparation Atmospheres and Promoters With DBD Plasma Fluidized Bed on MoS ₂ /CeO ₂ –Al ₂ O ₃ Catalyst for CO Sulfur‐Tolerant Methanation

ABSTRACT Based on the policy of building a beautiful China and the increasing demand for natural gas, the technology of converting coal to natural gas is receiving more and more attention. The Ni‐based methanation catalyst is prone to being poisoned and deactivated because coal‐based synthesis gas contains sulfides. Therefore, it is urgent to develop a sulfur‐tolerant methanation catalyst. MoS 2 /CeO 2 –Al 2 O 3 sulfur‐tolerant methanation catalysts were prepared with a DBD plasma fluidized bed. The effect of plasma atmospheres (Ar, H 2 , and air) and promoters (Ni and Co) on catalyst structure and performance was studied. It was found that catalysts pretreated in an air atmosphere exhibited the highest CO conversion, which is over 10% higher than that in Ar and H 2 , and CH 4 selectivity is also 8.94% higher than traditional calcination. Co doping resulted in more S vacancies in the catalyst, increasing its activity to 36.42%. Ni is more attached to the carrier in the form of oxides, forming Ni 3 S 2 after sulfurization, which covers some of the hydrogenation active sites and leads to a decrease in activity.