浸渍沉淀法制备活性炭负载Co-Mo双金属脱硫催化剂

Preparation of activated carbon-supported Co-Mo bimetallic catalyst by impregnation-precipitation method

以氧化改性活性炭为载体,尿素为沉淀剂,采用浸渍沉淀法制备了负载型Co-Mo催化剂,并用CO还原SO2反应作为模型反应考察了催化剂的催化活性。结果表明,催化剂焙烧温度500℃、Co/Mo物质的量比0.45、最佳反应条件(硫化温度为500℃、空速为7 000 mL/(g.h)、CO/SO2物质的量比为2∶1,反应温度为450℃)时,催化剂具有最好的催化活性和选择性。XRD表征结果表明,催化CO还原SO2反应的活性相为CoS2和MoS2,硫化温度影响活性相的形成。该催化剂稳定性好,反应运行24 h后活性仍能保持最高活性的99%。

Supported Co-Mo catalyst was prepared by impregnation-precipitation method using modified activated carbon as carrier and urea as precipitant.Catalytic activity of catalyst was studied by using the reduction of SO2 by CO.Under optimum reaction conditions（sulfidation temperature 500 ℃;GHSV=7 000 mL·g-1·h-1;CO/SO2 mol ratio = 2∶1;reaction temperature 450 ℃）,the best catalytic activity and selectivity were obtained for Co-Mo catalyst with calcination temperature was 500 ℃ and Co/Mo mol ratio = 0.45.Catalyst samples were characterized by X-ray powder diffraction（XRD） in order to relate the phase composition to the activation behavior and catalytic performance.The active phases of catalyst were detected as CoS2 and MoS2,and the formation of them were greatly dependent on the sulfidation temperature.And the catalytic activity of cobalt molybdenum catalyst decreased less than 1% after the reaction lasted for 24 h.