活性炭负载的纳米金催化剂上葡萄糖氧化工艺

Technology of Glucose Oxidation over Au/C Catalyst

采用溶胶固定法制备了一系列的Au/C纳米催化剂,进行了透射电镜(TEM)表征,用于常压下以氧气为氧化剂碱性溶液中葡萄糖氧化制备葡萄糖酸钠,并对最佳的催化剂进行了反应条件影响考察。结果显示,使用溶胶固定法制备的质量分数为1%的Au/C催化效果最佳,纳米金颗粒直径小于2 nm且分布均匀,其较佳反应条件为50℃,pH 9.5,氧气流量40 mL/min,催化剂0.22 g,水溶液中质量分数为7.5%的葡萄糖,葡萄糖在1 h内,选择性及转化率均可同时达到100%,反应的转化频率(Turnover Frequency,TOF)高达1 560 h-1。上述研究表明溶胶固定法能制备一定纳米金颗粒大小的Au/C催化剂,且在该多相催化剂上反应时间短,活性高,选择性高。

A series of Au/C nano-catalyst were prepared with sol-immobilization （SI） method and characterized under Transmission Electron Microscopy（TEM）. The performance of the catalyst was evaluated on the oxidation reaction of glucose to sodium gluconate in alkaline solutions with oxygen as the oxidant under atmospheric pressure at various operating conditions. The results show that 1.0% Au/C SI prepared catalyst with less than 2 nm uniformly distributed gold nanoparticles has the best reaction performance. A preferred set of reaction condition is 50 ℃, pH 9.5, the oxygen flow rate of 40 mL/min, catalyst 0.22 g, glucose concentration in the aqueous solution of 7.5%. At 1 h reaction time, both the glucose conversion and sodium gluconate selectivity are about 100%, and reaction turnover frequency （TOF） is up to 1 560 h^-1 . The above studies indicate that, SI method can make Au/C catalyst with a certain size of gold nanoparticles; the prepared catalyst has high activity and high selectivity, resulting in a short reaction time in heterogeneous reactions..