Various chromium-containing catalysts were tested for the total oxidation of trichloroethylene (TCE) as a model reaction for the catalytic combustion of chlorinated organic pollutants. A spinel-type cobalt chromite (CoCr2O4) among others was proven to be a very promising catalyst showing higher activity and higher CO2 selectivity than traditional alumina supported chromia. Even if both Cr3+ and Cr6+ species were observed on the surface of CoCr2O4, the Cr6+ species was stable under reducing environment. The presence of Cr3+-Cr6+ pair sites and the effect of redox treatments on the activity were investigated to explain the nature of possible active sites for TCE decomposition. Higher selectivity to CO2 of CoCr2O4 was ascribed to the abundance of its Cr3+ species, together with its activity for water gas shift reaction.

中文翻译：

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尖晶石型亚铬酸钴作为新型催化剂燃烧含氯有机污染物。

测试了各种含铬催化剂的三氯乙烯（TCE）的总氧化，以此作为氯化有机污染物催化燃烧的模型反应。尖晶石型亚铬酸钴（CoCr2O4）被证明是一种非常有前途的催化剂，与传统的氧化铝负载的氧化铬相比，具有更高的活性和更高的CO2选择性。即使在CoCr2O4的表面上同时观察到Cr3 +和Cr6 +物种，Cr6 +物种在还原环境下也是稳定的。研究了Cr3 + -Cr6 +对位点的存在以及氧化还原处理对活性的影响，以解释TCE分解可能的活性位点的性质。CoCr2O4对CO2的较高选择性归因于其Cr3 +种类丰富，以及其对水煤气变换反应的活性。