The Research On The NO+CO Reaction Over Cu/SiO₂ Catalyst Prepared By Sol-gel Method

A series of Cu/SiO2 catalysts were prepared by sol-gel method using tetraethylorthosilicate (TEOS). We studied some important facts in the process of sol-gel, such as catalysts, rate of water and alcohol, copper salts, the temperature of calcining, activation gas and temperature. We focus on the Cu/SiO2 catalysts, which are prepared by three different copper salts(Cu(NO3)2,Cu(CH3COO)2,CuCl2). Based on experimental results of XRD, BET, IR, H2-TPR and activity evaluation, the physical and chemical properties and catalytic performance of the catalysts for the NO+CO were investigated. The results showed that the catalysts with different copper salts were very different in the specific surface area, pore volume, surface OH and the surface distribution of Cu species. In the NO+CO reaction, Cu(Cl-)/SiO2 showed the highest activity in the Cu/SiO2 catalysts.The study results showed that in these catalysts different anions of salts affected the state of the metal Cu in the silica gel, the activity of Cu and the contacting between Cu and silica network. In Cu(Cl-)/SiO2 catalyst, Si-O-Cu species is formed, which is more useful for the NO+CO action. In the further study to the impact of Cl- , we wash the Cl- and only increase the Cl-. All of studies can inform the impact of the anion.At the same time, we prepare SiO2 by sol-gel and synthesize Cu/SiO2 catalysts by impregnation. These catalysts have lower activity. They have little difference between them.