在水蒸气存在下甲烷部分氧化制氢Ni-Cu/MgSiO催化剂的研究

采用表面复合氧化物MgO-SiO2(MgSiO)作为载体,用等体积浸渍法制备出Ni-Cu双金属催化剂。通过XRD,BET,TEM等方法对催化剂进行表征,用微反技术考察温度、空速及原料气组成对反应性能的影响。并与添加La2O3助剂的双金属催化剂反应性能相比较。实验结果表明,在Ni-Cu／MgSiO催化剂表面上存在着均匀分散的Ni,Cu金属颗粒;反应最佳条件为反应温度450℃、进料组成n(CH4)／n(O2)／n(H2O)=1／0.5／2.5以及甲烷空速1 200h-1,此时Ni-Cu／MgSiO催化剂上CH4转化率在96％以上,H2的选择性可达99％,而添加La2O3助剂后,CH4转化率及H2选择性均提高。

Study of Ni-Cu/MgSiO Catalyst for Methane Partial Oxidation to Produce Hydrogen in Presence of Steam

MgO-SiO2(MgSiO) supported Ni-Cu bimetallic catalyst was prepared by isovolumic impregnation. Surface structure of the catalyst was characterized by techniques of XRD, BET and TEM. Effects of reaction temperature , space velocity and feed composition on catalytic performance were studied with microreactor system technique, and the reaction results were compared with those of La2O3 promoted catalyst. Evenly-distributed Ni -Cu metallic particles existed on surface of catalyst. Under optimal conditions of reaction (reaction temperature 450 ℃ ;mole ration of CH4/O2/H2O = 1/0.5/2.5;velocity of methane 1 200 h-1)conversion of CH4 on the catalyst was over 96% ,and the selectivity of H2 was up to 99% . Addition of La2O3 as promoter, increased the conversion of CH4 and selectivity of H2.