Oxidation of mono- and polyalcohols with gold: Comparison of carbon and ceria supported catalysts

Aim of this work is the investigation of the gold catalysed liquid-phase oxidation of polyalcohols with both, primary and secondary alcohol groups, in order to evaluate the potential of gold catalysts to oxidise a secondary alcohol group in presence of a primary group. For that purpose we investigated the heterogeneously catalysed liquid-phase oxidations of n-propanol, as reference for the oxidation of the primary alcohol group only, of propylene glycol, where the competitive reaction can be examined and finally of glycerol, which is the target reaction due to known economic aspects. We report on the performance of ceria supported gold catalysts in these reactions and discuss the results in dependency of the specific surface area of the support, the catalyst and support preparation method and the catalyst activation conditions. Finally, in order to estimate the relative activity and selectivity of the ceria supported catalysts we compared the catalytic results with the performance of carbon and titania supported gold catalysts.     

氯化钙－正丙醇－水溶液稀释热

使用ＬＫＢ－２１０７型流动式微量热计测量了２８８．１５Ｋ，２９８．１５Ｋ和３０８．１５Ｋ下ＣａＣｌ_２－ｎ－Ｃ_３Ｈ_７ＯＨ－Ｈ_２Ｏ溶液的稀释热。混合溶剂中正丙醇摩尔分数Ｘα：０．００，０．１３，０．２５，０．５０，０．７５，０．８７和１．００。测量结果用扩展的Ｄｅｂｙｅ－Ｈｕｃｋｅｌ方程关联，计算了不同溶剂组成下溶液无限稀释热△Ｈ_Ｄ（ｍ＝０．５，Ｘα）。结果表明：Ｘα相同时，－△Ｈ_Ｄ随温度增加而增加；温度相同时，随Ｘα变化，当Ｘα≈０．８７时，－△Ｈ_Ｄ具最大值。