硝酸铈和尿素配比对甲醇水蒸气重整制氢CuO/CeO_(2)催化剂的影响

Effect of cerium nitrate and urea ratio on CuO/CeO_(2) catalyst for methanol steam reforming

以Ce(NO_(3))_(3)·6H_(2)O和尿素(CO(NH_(2))_(2))为原料,采用水热法合成CeO_(2)载体,再经等体积浸渍法负载活性组分得到CuO/CeO_(2)催化剂;通过XRD、N_(2)吸附-脱附、H_(2)-TPR等表征手段,探究Ce(NO_(3))_(3)·6H_(2)O和CO(NH_(2))_(2)配比对催化剂的结构、比表面积、还原性质的影响;并通过甲醇水蒸气重整制氢(MSR)反应对所制备CuO/CeO_(2)-x催化剂试样进行性能评价。实验结果表明,当Ce(NO_(3))_(3)·6H_(2)O和CO(NH_(2))_(2)的配比为1∶3时,制备的CuO/CeO_(2)-3催化剂表相CuO的还原温度较低、CuO-CeO_(2)间的相互作用较强,在MSR反应中表现出较好的催化活性;当反应温度为280℃、水醇摩尔比为1.2、甲醇水蒸气GHSV为800 h^(-1)的条件下,甲醇转化率可达92.8%。

Cerium nitrate(Ce(NO_(3))_(3)·6H_(2)O)and urea(CO(NH_(2))_(2))were used as the raw materials to synthesize CeO_(2) support by the hydrothermal method,and then CuO/CeO_(2) catalysts were prepared by impregnation method.The effects of the ratio of cerium nitrate and urea on the structure,specific surface area and reducibility of the catalysts were investigated by XRD,N_(2) adsorption-desorption and H_(2)-TPR characterization methods.The performances of the CuO/CeO_(2)-x catalyst samples were evaluated in methanol steam reforming(MSR)reaction.The results showed that when the ratio of cerium nitrate and urea was 1∶3,the surface CuO phase in the CuO/CeO_(2)-3 catalyst had a lower reduction temperature and stronger interaction with CeO_(2),and the catalysts showed better catalytic activity in MSR reaction.When the reaction temperature was 280℃,the molar ratio of water to methanol was 1.2,and the GHSV of methanol vapor was 800 h^(-1),the conversion of methanol was 92.8%.