Study On The Catalytic Performance Of Ni-Cu Catalysts For Partial Oxidation Of Methane To Syngas

Catalytic partial oxidation of methane to synthetic gas (POM) is an effective way to make use of methane, with the advantages of low consumption, high CO and H2 selectivity, and the proper ratio of n(H2)/n(CO) for further methanol and F-T synthesis. The key to industrialization is developing Ni based catalysts with high activity and good stability .In this article, Ni-Cu catalysts were first designed and prepared, their catalytic performance was evaluated in the fixed bed reactor and their physicochemical properties were carefully characterized.Firstly, the effect of Cu introduction to Ni/La2O3 was investigated. The results show that well-defined crystalline structure has been formed after calcination at 750℃. The sample prepared by coimpregnation shows better catalytic activities than the other two samples by sequential impregnation. The catalytic activity is greatly enhanced after introduction of proper amounts of Cu, but decreased when large amount of Cu is added. The Cu and Ni forms an alloy, which decreases the Ni particle size and promotes its dispersion. The synergism between them increases the active sites, thus promotes the activity and stability of the catalyst.Secondly, the Ni-Cu/Al2O3 catalyst was prepared by coimpregnation method. The results show that well-defined crystalline structure has been formed after calcination at 650℃. The effect of calcination temperature, Ni content and reaction temperature on the catalytic performance was investigated, and the results show that the catalyst after calcination at 650℃, under atmospheric pressure and with CH4:O2:N2 = 2:1:4, exhibits the highest activity.Pass the stability testing, discovering Ni-Cu catalyst being still very stable, Conversion rate of methane kept above 96% and having fairly good resisting accumulating the charcoal ability.