微乳液在制备C_2含氧化合物合成催化剂中的应用

The Application of Microemulsion in the Preparation of Catalysts for CO Hydrogenation to C_2 Oxygenates

对微乳液法在制备C2含氧化合物合成催化剂中的应用做了较为详细的综述。从制得纳米粒子与载体的结合方式,主要有3种方法:微乳液同步合成法,微乳液沉积法和微乳液浸渍法。目前报道较多的是第一种方法,制得的Rh/SiO2催化剂具有较好的CO加氢生成C2含氧化合物的活性和选择性,但存在金属包埋的问题。微乳液沉积法可部分解决金属包埋问题,但金属与载体之间的化学作用力不强而导致催化剂热稳定性较差。微乳液浸渍法可以通过保持水核中金属离子在浸渍过程中处于未还原状态从而避免上述这些问题,虽然该法仅用于F-T合成催化剂的制备,但催化性能优越,产物中甲烷选择性非常低,值得尝试用于C2含氧化合物合成催化剂的制备。

The application of microemulsion inthe preparation of catalysts for CO hydrogenation to C2 oxygenates were briefly reviewed. Three methods are oftenused to support the nano metal particles onto the carrier： microemulsion synchronous synthesis, microemulsion deposition and microemulsion impregnation, of which the first one is widely reported to prepare Rh/SiO2 catalyst that exhibits high performance for the formation of C2 oxygenates. However, the metal particles are partially embedded. Microemulsion deposition method can partly solve this problem, but weak chemically interaction between metal and support leads to low thermo-stabihty. High catalytic performance with very low selective to methane is achievable when microemulsion impregnation method is employed to prepare FTS catalyst with high stability, and it deserves to be applied in the preparation of C2 oxygenates synthesis catalyst.