铜基水滑石材料设计及其催化甘油氢解制备1,2-丙二醇研究

Large amounts of surplus glycerol were produced in the process of biodiesel production, and therefore finding out reasonable outlets to make use of glycerol has become a more and more important research subject. Hydrogenolysis of glycerol to 1, 2-propylene glycol is one of the promising approaches to transforming glycerol. The development of highly efficient catalysts is the key factor in the successful hydrogenolysis of glycerol. In the present study, the magnetic and easily separated and recycled CuFeMg catalysts derived from layered double hydroxides for the hydrogenolysis of glycerol were synthesized. Furthermore, to enhance the performance of the CuFeMg catalysts, the stable and highly dispersed CuFeMg /CNT catalysts were prepared by the self-assembling method, which is formed in-situ growth on the functionalized-carbon nanotubes with polyacrylic acid (or 3, 4, 9, 10-perylene tetracarboxylic acid). The above research on the catalysts could provide new ideas and new methods in the hydrogenolysis of glycerol and promote the sustainable development of biodiesel production.

生物柴油产业的迅速发展产生了大量副产物甘油，寻找合理的途径转化甘油已成为亟待解决的问题。当前，甘油氢解生产1,2-丙二醇被认为是最具发展潜力的途径之一，而开发高效催化剂是甘油氢解顺利进行的关键因素。本研究利用CuFeMg水滑石为前驱体，制备磁性、易分离回收的Cu基水滑石催化剂用于甘油氢解反应；并进一步利用碳纳米管为骨架，通过聚丙烯酸、苝四羧酸对其进行非共价修饰，与CuFeMg水滑石进行原位可控组装，制备稳定、高分散的负载型纳米铜基催化材料，提高其在甘油氢解反应中的催化性能。以上催化剂的研究将为甘油氢解提供新思路、新方法，推动生物柴油产业的可持续发展。

通过共沉淀法制备了一系列CuMgFe水滑石(CuMgFe-LDH)为前驱体的磁性Cu基催化剂，并应用于催化甘油氢解制1,2-丙二醇反应。当Cu含量为9 %， H2压力为2 MPa，（Cu+Mg)/Fe 摩尔比为4的CuMgFe-4LDO催化剂用量为0.6 g，75%甘油水溶液8 g，180 ℃反应10 h时，甘油转化率及1,2-丙二醇选择性分别为47.8%及97.5%。CuMgFe-4LDO催化剂较高的活性与其表面较高的Cu含量、较强的碱性及较好的吸附活化氢能力有关。利用外加磁场易对CuMgFe-4LDO催化剂进行分离回收，CuMgFe-4LDO催化剂展示出较高的稳定性。此外，通过芘四羧酸（PTCA）对碳纳米管(CNT)进行非共价修饰，并与CuFeMg-LDH进行组装，获得一系列CuFeMg-LDO/CNT催化剂。当PTCA/CNT质量比为0.2，CNT-PTCA/9CuMgFe-3LDO质量百分比为10%，H2压力为2 MPa，9CuMgFe-3LDO/10CNT-0.2PTCA催化剂用量为0.5 g，75%甘油水溶液8 g，180 ℃反应10 h，甘油转化率及1,2-丙二醇选择性分别为53.5%及97.3%。9CuMgFe-3LDO/10CNT-0.2PTCA催化剂较高的活性源于其较高的表面Cu物种分散度及较强的吸附活化氢能力。以上催化剂的研究将为甘油氢解转化提供新思路、新方法，推动生物柴油产业的可持续发展。