摘要
当负载型Co催化剂Co含量小于5％时,对F-T反应的催化活性很低.原因是钴的氧化物与载体相互作用影响了钴的还原度.例如Co负载在Al<sub>2</sub>O<sub>3</sub>上,占据四面体晶格位置后较难被还原.当负载量低时,这些位置优先被占据,所以随着钴负载量降低,被还原的百分比降低.由此可见,要想获得金属含量低。
Three kinds of Co-Cu-K/Al2O3 catalyst were prepared by the Sol-vated Metal Atom Impregnation (SMAI) method. The preparation procedures for the catalysts were the same not including the de-toluene temperature. The results of TEM, XRD and magnetic measurement showed that Co and Cu existed basically as free particles, and no Co-Cu alloy was formed. As the de-toluene temperature raised, the particle size of Co and Cu increased. The dispersivity of Co was higher than that of Cu. The results of magnetic measurement indicated that Co on all these catalysts exhibited super-paramagnetic properties. XPS and Auger spectra revealed that Co and Cu were mainly in the state of zero valence.
