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 decr...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.展开更多
文摘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.
