Study On CuO-CeO₂ Catalyst Prepared By Direct Solvothermal Method And Its Catalytic Performance For CO Oxidation

In recent years,due to the low catalytic cost of the CuO-CeO₂ system,it has been extensively studied in the CO catalytic oxidation reaction and has received widespread attention as a substitute for noble metal oxide catalysts.In this paper,the direct solvothermal method is used to prepare CuO-CeO₂ catalyst.The main research contents are as follows:（1）The CuO-CeO₂ catalyst with a CuO content of 20 mol%was prepared by the solvothermal-deposition method and its performance in catalyzing CO oxidation was investigated and compared with the direct solvothermal method.The results show that the CuO-CeO₂ catalyst prepared by the direct solvothermal method not only has higher activity,but it has the advantages of simpler preparation process,energy saving and time saving compared with the solvothermal deposition method.In addition,it can be concluded that the catalyst prepared by the direct solvothermal method has better water resistance.（2）The investigation results of CuO content show that with the increase of CuO content,the catalyst activity of the catalyst presents a volcanic curve change trend.When the CuO content is 20 mol%,the catalyst activity obtained is the highest which the CO conversion reaches 90%at 86 ^oC.And it can be found that the ability of CuO-CeO₂ catalyst to catalyze CO oxidation reaction at low temperature depends more on the number of oxygen vacancies and the interaction between CuO and CeO₂.（3）The inspection results of the calcination temperature show that with the increase of the calcination temperature,the activity of the catalyst first increases and then decreases.When the calcination temperature is 450-650 ^oC,the catalyst has good thermal stability.When the calcination temperature is 550 ^oC,the catalyst contains more active center Cu⁺,which can better promote the adsorption of CO on the catalyst surface.（4）The performance of CuO-CeO₂ catalysts with different metal salt precursors prepared by direct solvothermal method for CO oxidation also investigated.The results show that the catalyst prepared when the copper salt precursor is Cu（Ac）₂·H₂O exhibits the best CO catalytic oxidation performance.However,in the water resistance test,the catalyst prepared with Cu（Ac）₂·H₂O showed weaker water resistance,while the catalyst prepared with Cu（NO₃）₂·3H₂O whose activity was second only to it showed excellent water resistance.