电导研究贵金属Pt在Co3O4还原过程中的作用

通过考察Co3O4在还原过程中电导率的变化, 并结合程序升温还原方法, 对贵金属Pt的作用进行了研究. 另外, 研究了Co3O4在氢气、氧气和合成气气氛中电导率的连续变化过程, 以便进一步了解Co3O4在实际费-托合成反应条件下的氧化-还原历程, 以及贵金属Pt在该过程中的作用.

Effect of Pt on Co3O4 Reduction via Electrical Conductance Method

The reduction features of Co_ 3 O_ 4 and Pt/Co_ 3 O_ 4 were studied by electrical conductivity in this paper. Combined with the TPR results, it is concluded that the presence of noble metal Pt could significantly decrease the reduction temperature of Co_ 3 O_ 4 . In addition, the electrical conductance ratios of Co_ 3 O_ 4 and Pt/Co_ 3 O_ 4 under different atmospheres, which are in a consecutively changing sequence of hydrogen, oxygen and syngas, were also investigated. It is found that the cobalt oxides resulted from the oxidation of Co metal under oxygen atmosphere can be re-reduced by the syngas in the presence of Pt noble metal. Because the electrical conductance study was conducted at 493 K, which is close to the typical reaction temperature of Fischer-Tropsch synthesis with cobalt based catalysts. It is reasonably speculated that the presence of Pt is beneficial to inhibiting the oxidation of cobalt metal during the Fischer-Tropsch synthesis, and thus eliminating the deactivation of cobalt catalyst.