Surface structure and reaction performances of highly dispersed and supported bimetallic catalysts


Autoria(s): Lin, LW; Yang, WS; Jia, JF; Xu, ZS; Zhang, T; Fan, YN; Kou, Y; Shen, JY
Data(s)

01/12/1999

Resumo

Surface structures of Pt-Sn and Pt-Fe bimetallic catalysts have been investigated by means of Mossbauer spectroscopy, Pt-L-III -edge EXAFS and H-2-adsorption. The results showed that the second component, such as Sn or Fe, remained in the oxidative state and dispersed on the gamma-Al2O3 surface after reduction, while Pt was completely reduced to the metallic state and dispersed on either the metal oxide surface or the gamma-Al2O3 surface. By correlating the distribution of Pt species on different surfaces with the reaction and adsorption performances, it is proposed that two kinds of active Pt species existed on the surfaces of both catalysts, named M-1 sites and M-2 sites. M-1 sites are the sites in which Pr directly anchored on the gamma-Al2O3 surface, while M-2 sites are those in which Pt anchored on the metal oxide surface. M-1 sites are favorable for low temperature H-2 adsorption, and responsible for the hydrogenolysis reaction and carbon deposition, while M-2 sites which adsorb more H-2 at higher temperature, are more resistant to the deactivation due to less carbon deposition, and provide major contribution to the dehydrogenation reaction.

Identificador

http://159.226.238.44/handle/321008/86609

http://www.irgrid.ac.cn/handle/1471x/180956

Idioma(s)

英语

Fonte

林励吾 杨维慎 贾继飞 徐竹生 张涛 范以宁 寇元 沈剑一.Surface structure and reaction performances of highly dispersed and supported bimetallic catalysts,中国科学(B辑); 1999;42(6):571-580,1999,():-

Palavras-Chave #metallic catalysis #isobutane #dehydrogenation #M-1 sites #M-2 sites
Tipo

期刊论文