碳纳米管负载的铂催化剂对柠檬醛选择加氢及CO微分吸附热研究

Carbon nanotube is found to be a novel support for the selective hydrogenation of citral in this paper. Selective hydrogenation of citral was carried out in an autoclave at 5 MPa and 323 K. The results indicate that the selectivity of the products, unsaturated alcohols, is about 86 over Pt/CNTs catalyst and 48 over Pt/XC-72 catalyst, respectively. The differential heat of CO adsorption measured by microcalorimetry is firstly used to probe surface adsorption sites of platinum catalyst supported on carbon nanotubes. The experimental results indicate that the Pt/CNTs catalyst shows a higher initial differential heat of CO adsorption(126 kJ/mol) than the Pt/XC-72 catalyst(106 kJ/mol).

黏红酵母CCZU-G5选择性加氢柠檬醛合成香叶醇

以黏红酵母CCZU-G5为菌株,通过对菌体培养时间、辅底物葡萄糖浓度、底物柠檬醛初始用量、菌体浓度及反应时间等条件的研究,考察其对柠檬醛选择性加氢反应的影响。结果表明,当培养28 h后,菌体达到对数生长期末期,此时菌体数量及活力处于较高水平。利用此时的菌体进行加氢反应过程中,最佳反应条件为:辅底物葡萄糖浓度40 g/L,底物柠檬醛添加浓度4 g/L,菌体浓度0.4 g/mL,反应时间22 h。在此条件下,柠檬醛转化率及对香叶醇的选择性分别达88.6%与95.2%。此研究为生物合成香叶醇的工业化奠定基础。