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采用前掺杂法、沉积-沉淀法和浸渍法制备了氧化锰八面体分子筛(OMS-2)负载Pt催化剂(Pt/OMS-2),对所制催化剂进行了结构和织构表征。并研究了不同制备方法和沉积-沉淀法中不同制备(Pt负载量和溶液的pH值)对Pt/OMS-2催化氧化CO性能的影响。结果表明,沉积-沉淀法制备的Pt/OMS-2-DP催化剂活性最好(T100=100℃)。这与Pt/OMS-2-DP催化剂中Pt颗粒大小及OMS-2载体与Pt之间存在强相互作用有关。Pt负载量明显影响Pt/OMS-2-DP催化剂的催化活性,3Pt/OMS-2-DP催化剂(Pt=3.0 wt%)催化活性最高,这是由于适当Pt负载量,Pt颗粒较小,并与载体OMS-2的相互作用较强,能较好地活化OMS-2晶格氧。pH值对Pt/OMS-2-DP催化剂催化性能影响较大,这与OMS-2的等电点和Pt在不同溶液中存在不同Pt配位体形式有关。
The Pt / OMS-2 catalyst was prepared by pre-doping method, deposition-precipitation method and impregnation method. The structure and texture of the catalyst were characterized. The effects of different preparation methods (Pt loading and pH value of solution) on the performance of Pt / OMS-2 catalysts for CO oxidation were studied in different preparation methods and deposition-precipitation methods. The results show that Pt / OMS-2-DP catalyst prepared by precipitation-precipitation method has the best activity (T100 = 100 ℃). This is related to the Pt particle size in Pt / OMS-2-DP catalyst and the strong interaction between OMS-2 and Pt. The catalytic activity of Pt / OMS-2-DP catalyst was significantly affected by the loading of Pt. The catalytic activity of 3Pt / OMS-2-DP catalyst (Pt = 3.0 wt%) was the highest due to the smaller Pt particle size Strong interaction with the carrier OMS-2, can better activate OMS-2 lattice oxygen. The pH value has a great influence on the catalytic performance of Pt / OMS-2-DP catalyst, which is related to the isoelectric point of OMS-2 and the existence of different Pt ligands in different solutions.