铂基催化剂对甲醛的室温催化净化性能

Catalytic purification performance of formaldehyde on Pt-based catalysts at room temperature

采用直接沉淀还原法制备了新型TiO2负载型铂基催化剂，并对该催化剂在甲醛室温完全催化氧化净化反应中的活性、稳定性和适用性进行研究。结果表明：当铂负载量（质量分数）仅为0．10％时，制备的催化剂即可在室温使甲醛净化率达到97％，而且在50h的稳定性测试中，甲醛净化率始终维持在95％以上；同时该催化剂在甲醛质量浓度为3—50mg／m^3和空气湿度为36％～90％较大变化范围内，也可使甲醛室温净化率始终在90％以上。通过表面形貌和粒径分布分析可知，催化剂中活性组分铂颗粒以2～5nm粒径尺度在TiO：载体表面均匀分散．这应该是该催化剂表现出优越甲醛室温催化净化能力的主要原因。

The new TiO2 supported Pt-based catalysts were prepared by direct precipitation and reduction method. And the activity, stability and applicability of the as-prepared catalysts in formaldehyde catalytic purification at room temperature were also studied. The results show that the suitable Pt loading is as low as 0.10%, over which the removal efficiency of formaldehyde can reach 97% and also keep above 95% during the stability test for 50 h. Meanwhile, the formaldehyde removal efficiency on the as-synthesized catalysts remains above 90%, while the inlet formaldehyde concentration and inlet relative humidity varies in the range of 3-50 mg/m^3 and 36% -90% respectively. Further from the analysis of TEM and size distribution of Pt particles, it can be found that the active Pt particles are uniformly dispersed on the surface of TiO2 supporter with small particle size of 2 -5 nm, which results in the extinguished formaldehyde catalytic purification performance at room temperature.