论文部分内容阅读
用TPR法研究了烃类蒸气转化制氢催化剂还原性能。发现这类催化剂的还原符合核化模型。镍与催化剂中其它组分相互作用影响催化剂的还原,MgO和水泥的加入均提高了NiO的还原温度,稀土氧化物的加入可降低NiO-MgO体系的还原温度。由TPR曲线峰形分析求得了RKN,TDRE-3和ICI-46-1以及其它含CeO_2催化剂还原动力学参数。发现CeO_2的加入减少了催化剂的还原活化能,且还原活化能与镍的分散度之间有较好的对应关系,即镍铈比(Ni/Ce)分散得越均匀,则还原活化能越低。提出了CeO_2促进还原的机理。
TPR method was used to study the catalytic performance of hydrocarbon steam reforming. The reduction of these catalysts was found to be consistent with the nucleation model. The interaction between nickel and other components of the catalyst affects the reduction of the catalyst. The addition of MgO and cement both increase the reduction temperature of NiO. The addition of rare earth oxides can reduce the reduction temperature of NiO-MgO system. The reduction kinetic parameters of RKN, TDRE-3 and ICI-46-1 and other catalysts containing CeO 2 were obtained from the peak shape analysis of TPR curve. It is found that the addition of CeO 2 reduces the reduction activation energy of the catalyst and the reduction activation energy has a good correspondence with the dispersion of nickel. That is, the more uniform the Ni / Ce ratio, the lower the reduction activation energy . The mechanism of CeO 2 promoted reduction was proposed.