钴源对Co/SBA-15催化乙醇水蒸气重整反应的影响

Influences of Cobalt Sources on the Catalytic Performance of Co/SBA-15 in Ethanol Steam Reforming Reaction

以介孔分子筛SBA-15为载体,分别以硝酸钴、乙酸钴、硫酸钴和氯化钴为钴源,采用浸渍法合成了4种催化剂。采用XRD、N_2物理吸附-脱附等技术对催化剂的物相和结构进行表征,并研究了其在乙醇水蒸气重整反应中的催化特性。结果表明,以醋酸钴为钴源制备的催化剂经过焙烧后有C生成,以硫酸钴为钴源制备的催化剂经焙烧后很难生成钴的氧化物且较难还原,这都对催化剂的活性产生了一定的影响。另外,在反应温度为550℃、水醇体积比为10∶1的条件下对比发现,以硝酸钴为钴源制备的催化剂的催化效果最好,氢气选择性可达68.4%,乙醇转化率可达93.49%。

Four catalysts were synthesized by impregnation method using SBA-15 as carrier and cobalt dioxide, cobalt acetate, cobalt sulfate and cobalt chloride as cobalt sources, respectively.The phase and structure property of the catalysts were characterized by means of XRD and N2 adsorption-desorption.The catalytic properties were studied by ethanol steam reforming reaction.Results show that after calcination the catalyst prepared with cobalt acetate has carbon deposition, while there is almost no cobalt oxide found in the catalyst prepared with cobalt sulfate after roasting and reducing, which has impact on the activity of catalysts.In addition, under the reaction conditions of 550℃ and the volume ratio of water to alcohol of 10∶1, cobalt nitrate is the best cobalt source, from the viewpoint of catalytic efficiency, showing hydrogen selectivity of 68.4% and ethanol conversion of 93.49%.