| Nowadays,air pollution is increasingly concerned by people,and all kinds of toxic and harmful gases in the air are also becoming hot topics in the news media,CO is one of them.Catalytic oxidation is the best way to remove CO.Therefore,it is of great significance to explore more efficient and economical catal ysts in the field of CO catalytic oxidation.In this study,the application of Cu-Fe composite oxide catalyst in CO catalytic oxidation was investigated,and it was divided into three parts,including the influence of different copper load and calcination temperature,the influence of different preparation methods and preparation parameters,and the influence of hydroxyl group on the activity of Cu-Fe catalyst.The first part of the experiment shows that show that when the load of copper 10%,calcination temperature is 400 ℃,Cu-Fe catalyst has the best catalytic oxidation activity.In the second part,three common preparation methods include coprecipitation,deposition and urea combustion have been experimentally compared.It was found that the materials prepared by co-precipitation method had more advantages in both structural characteristics and catalytic oxidation activity.On the basis of the coprecipitation method we continue to explore the influence of different pH value and precipitation agent,it is found that the catalyst prepared with NaOH as the precipitant and pH controlled at 8 had larger specific surface area,surface-active oxygen amount and better oxidative reducibility,thus showing better catalytic oxidation activity in the CO catalytic oxidation reaction.The third part explores the influence of hydroxyl group on the two kinds of catalysts of pure iron and Cu-Fe which are only dried or calcined.The results show that for the uncalcined of iron-based catalyst exist a large number of hydroxyl groups,which could make the catalyst exist in an amorphous and amorphous state,so the catalyst had a larger specific surface area,increased the contact area between the catalyst and the reaction gas,and thus effectively promoted the catalytic reaction.At the same time,hydroxyl can effectively promote the adsorption and activation of CO by the catalyst,and as one of the important substances to provide reactive oxygen in the catalytic oxidation of CO,its existence is one of the important reasons for the good catalytic oxidation activity of the uncalcined catalyst.In addition,it was found that the interaction of elements in the Cu-Fe catalyst is also an important reason for the influence of catalyst on the oxidation activity of CO. |
