脉冲放电协同Ag改性Mn-TiO2/分子筛催化剂去除甲醛

为进一步提高Mn-TiO2/分子筛催化剂和等离子体协同的催化活性，增加CO2选择性，减少O3产量。以5A分子筛为催化剂载体，采用浸渍法并利用Ag改性制备了Ag-Mn-TiO2/分子筛催化剂，并运用XRD、SEM、EDS和FT-IR等技术对催化剂进行了表征。在针-板式高压脉冲反应器中研究了Ag的负载量与焙烧温度对Ag-Mn-TiO2/分子筛催化剂的催化活性、CO2选择性和O3的产量的影响。结果表明：掺杂Ag后，促进Mn价态向+4价转变，提高了Mn-TiO2/分子筛催化剂活性；焙烧温度为500℃时，Ag和Mn在分子筛上分布均匀，有利于Ag和Mn氧化物晶粒成长。当脉冲电压20 kV，Ag负载量为4%时，Ag-Mn-TiO2/分子筛催化剂的甲醛去除率达到97.6%，O3浓度为99.4 mg·m-3，CO2选择性为50.2%。

Degradation of formaldehyde by pulsed discharging plasma combined with Ag-modified Mn/TiO2-molecular sieve catalyst

In order to further improve the synergic catalytic activity of Mn-TiO2/molecular sieve catalyst and plasma, increase the selectivity of CO2 and reduce the output of O3.5A molecular sieve was treated as the support of catalyst, Ag-Mn-TiO2 molecular sieve catalysts were prepared by applying impregnation method and modified it with Ag. The catalysts were characterized by applying XRD, SEM, EDS and FT-IR technologys. The effects about the load of Ag and calcination temperature to the catalytic activity, CO2 selectivity and output of O3 of Ag-Mn-TiO2/molecular sieve catalyst were investigated in a needle-plate high voltage pulse reactor. The experiment results show that the doping of Ag could promote the transformation of Mn valence state to the+4 price and improve activity of the Mn-TiO2/molecular sieve catalyst;when calcination temperature is 500℃, Ag and Mn distribute uniformly on the molecular sieve,it is conducive to the growth of Ag and Mn oxide grain. When the pulse voltage is 20 kV, the load of Ag is 4%, the formaldehyde removal rate of Ag-Mn-TiO2/molecular sieve catalyst is 97.6%, the concentration of O3 is 99.4 mg·m-3, the selectivity of CO2 is 50.2%.