所属领域：
钍基熔盐堆核能系统
资源类型：
天文学、地球科学
/ 地质学
文献作者：
EISEN, MS; MARKS, TJ
文献发表年份：
1994
文献期刊：
JOURNAL OF MOLECULAR CATALYSIS
文献摘要：The adsorption of organoactinide complexes on dehydroxylated alumina (DA) yields coordinatively unsaturated, highly active catalysts for several demanding chemical transformations. Thus, in the case of Th(eta3-allyl)4 supported on dehydroxylated gamma-alumina (DA), facile arene hydrogenation and alkane activation processes can be effected in slurry reactions at 90-degrees-C and P(H2) = 30-180 psi. Benzene reduction occurs at a turnover frequency of almost-equal-to 25000 h-1 per active site and cyclohexane C-H exchange with D2 at almost-equal-to 1300 h-1 per active site. Active site characterization using D2O poisoning, hydrogenolysis, and CH3Cl dosing indicates less-than-or-equal-to 8 +/- 1 % of the Th surface sites are catalytically significant. EPR and XPS spectroscopy provide no evidence for Th oxidation states less than +4. The mechanisms for the above processes are discussed in terms of electrophilic ''four-center'' activation processes in which the active sites appear to bear sterically significant, nonhydridic ancillary ligation.
文献类型： Article
文献语种： English
关键词： ALKANE ACTIVATION; ALLYL COMPLEXES; ARENES; HETEROGENEOUS CATALYSIS; HYDROGENATION; THORIUM
文献作者地址： TECHNION ISRAEL INST TECHNOL,DEPT CHEM,IL-32000 HAIFA,ISRAEL; NORTHWESTERN UNIV,DEPT CHEM,EVANSTON,IL 60208