甲醇在CeO_2担载Pd催化剂上分解机理的研究

Studies on Mechanism of Methanol Decomposition over Pd/CeO_2 Catalyst

采用原位红外 ( in-situ FTIR)技术对甲醇在 Ce O2 和 Pd/ Ce O2 催化剂上的吸附和反应进行了研究 ,提出一个新的甲醇分解反应机理模型 .甲醇在 Ce O2 上容易吸附并结合其晶格氧生成甲酸盐物种 ,而甲醇分解的产物氢被 Pd活化后 ,溢流到 Ce O2 上促进了甲酸盐物种的分解 .Cl- 的存在加强了 Pd/ Ce O2 催化剂与氢的相互作用 ,Pd和 Ce O2 通过对氢和氧物种的作用对甲醇分解反应的过程表现出协同效应 .

The interaction between hydrogen and CeO 2 support and Pd/CeO 2 catalysts is characterized by TPR and H 2-TPD, while the adsorption and decomposition of methanol over CeO 2 and Pd/CeO 2 catalysts were studied by in-situ FTIR technique, then a new model of the mechanism for the methanol decomposition over Pd/CeO 2 catalyst was proposed. It was found that the lattice oxygen of CeO 2 was active towards oxidation of the adsorbed methanol to form formate species, which were then reduced by the hydrogen produced and activated on Pd. The anion Cl\+- promoted the interaction between hydrogen and Pd/CeO 2 catalyst, so a synergistic effect between Pd and CeO 2 was proved by their action of lattice oxygen and hydrogen.