甲烷在Ni/TiO_2催化剂表面的活化

考察了Ｎｉ／ＴｉＯ２催化剂甲烷部分氧化和二氧化碳重整制合成气的反应活性，实验表明，以ＴｉＯ２为载体的镍系催化剂对于甲烷部分氧化制合成气反应具有较好的活性，尤其对Ｈ２的选择性较高，对二氧化碳重整制合成气反应具有较好的低温反应活性．采用脉冲－质谱在线分析等技术，在无气相氧条件下向Ｎｉ／ＴｉＯ２催化剂脉冲ＣＨ４，发现甲烷在催化剂表面的活化（转化）及其氧化产物的选择性与金属催化剂表面氧的浓度密切相关．ＣＨ４与Ｎｉ／ＴｉＯ２催化剂作用过程中存在明显的氢溢流和氧溢流现象，可能是这种溢流效应使得Ｎ／ＴｉＯ２催化剂具有良好的反应活性和抗积碳性能．

Activation of Methane over Ni/TiO_2 Catalyst

The reactions of methane partial oxidation (POM) and methane reforming with CO2 to produce syn- thetic gas over Ni/TiO2 catalyst were studied. The catalyst shows good catalytic performance with high H2 selec- tivity for the POM reaction and good low temperature activity for the reaction of methane reforming with CO2. The activation of methane over Ni/TiO2 catalysts was investigated using MS-pulse technique in the absence of gaseous oxygen. It was found that methane activation and its oxidation products were determined by the concentration of surface oxygen species of the catalyst. Both oxygen and hydrogen spillover phenomena were observed during the interaction of methane with Ni/TiO2. The spillover oxygen and hydrogen species over the catalyst may be respon- sible for the good activity and carbon resistance ability of the Ni/TiO_2 catalyst.