沉淀方式对Ni-Cu/ZrO_2-CeO_2-Al_2O_3催化剂甲烷自热重整制氢性能的影响

Effect of Precipitation Mode on Autothermal Reforming of Methane over Ni-Cu/ZrO_2-CeO_2-Al_2O_3 Catalyst

以Na2CO3为沉淀剂,分别采用反加法、并流法和正加法制备了Ni-Cu/ZrO2-CeO2-Al2O3催化剂,催化剂中Ni负载量(质量分数)为10%。采用XRD和H2-TPR方法表征了催化剂的结构及还原性能,并考察了催化剂对甲烷自热重整制氢反应的活性。实验结果表明,反加法和正加法制备的催化剂中CeO2-ZrO2固溶体的晶粒较大,且各种氧化物独立存在;并流法制备的催化剂能很好地抑制非活性组分NiAl2O4的形成,NiO分散性较好。在反应温度为650～850℃时,并流法制备的催化剂的催化性能明显高于正加法和反加法制备的催化剂。

Ni-Cu/ZrO2-CeO2-Al2O3 catalysts （R-Cat, C-Cat and N-Cat） were prepared with reverse adding mode, co-current flow mode and normal adding mode using Na2CO3 as precipitant, respectively. Ni loadings （mass fraction） of the catalysts were all 10%. Structures and reduction properties of the catalysts were characterized by means of XRD and H2-TPR, and their catalytic performances in autothermal reforming of methane to hydrogen were investigated. Results showed that crystal particle sizes of both N-Cat and R-Cat catalysts were a little bigger, and various oxide species existed independently. C-Cat significantly inhibited formation of inactive NiAl2O4 and facilitated the dispersion of NiO. C-Cat showed the best catalytic activity among the three catalysts for autothermal reforming of methane to hydrogen in the temperature rang of 650 - 850 ℃.