过渡金属对Pt/SiC催化剂上CO氧化性能的影响

Effect of transition metal promoters on CO oxidation over Pt/SiC catalyst

以SiC为载体、Pt为活性组分、过渡金属Fe、Co和Ni为助剂,采用浸渍法制备CO氧化催化剂。考察浸渍方法、助剂及其负载量、空速和催化剂焙烧温度等对Pt/SiC催化剂性能的影响。结果表明,助剂的加入提高了活性组分Pt在载体表面的分散度,并产生一定的相互作用,从而提高了催化剂活性,其中,铁助剂的助催化效果较好。共浸渍法制备的催化剂的催化活性优于分步浸渍法,Pt-Fe/SiC催化剂制备中焙烧温度500℃时,催化剂活性较佳,适量Fe助剂的添加能够显著提高Pt/SiC催化剂的活性。

Pt/M/SiC CO oxidation catalysts were prepared by impregnation, using SiC as the support, platinum as the active constituent and transition metals （ Fe, Co and Ni ） as the promoters. Effects of different transition metals and their loadings, impregnation procedures, space velocity and calcination temperature on catalytic properties of the Pt/SiC catalysts were investigated. The results showed that addition of transition metals remarkably enhanced the catalytic activity by improving Pt dispersion and the interaction between Pt and transition metals. The catalyst promoted by Fe exhibited the highest activity. The catalyst prepared by co-impregnation was superior to those prepared by stepwise impregnation. Appropriate loadings of Fe apparently enhanced catalytic activity of Pt/SiC. The optimal calcination temperature for Pt-Fe/SiC catalyst was 500℃.