CNT/CS/Ni复合材料的制备及催化性能研究

Researches on the Preparation of Carbon Nanotubes/Chitosan/Nickel Composite Material and Their Performance

通过溶液共混法将碳纳米管超声分散到壳聚糖的醋酸水溶液中,然后过滤、烘干得到碳纳米管/壳聚糖复合材料。将该复合材料吸附金属镍离子后,并用NaBH4溶液还原制备碳纳米管/壳聚糖/镍的复合材料(CNT-CS-Ni),研究CNT-CS-Ni复合材料催化硼氢化钠(NaBH4)还原对硝基苯酚(4-NP)的反应活性。探讨硼氢化钠的量、反应温度、催化剂的量等因素对反应活性的影响。研究结果表明:CNT-CS-Ni对NaBH4催化还原对硝基苯酚的活化能为50.28kJ mol-1,活化焓为47.66 kJ mol-1和活化熵-99.84 J mol K-1。NaBH4还原对硝基苯酚的反应速率常数与CNT-CS-Ni的量近似成线性增大。

Carbon nanotube/chitosan composite materials were prepared by blending carbon nanotube with chitosan-acetic acid solution by ultrasonic technique, then filtering and drying. Carbon nanotube/chitosan composite materials then adsorbed nickel ion and were reduced by NaBH4 solution, lastly converted to carbon nanotubes/chitosan/nickel composite materials （CNT-CS-Ni）. The catalysis reaction activity of CNT-CS-Ni was studied by reduction of nitro phenol （4 - NP） with sodium borohydride （NaBH4） solution. The influencing factors of the reaction activity on the amount of sodium borohydride, reaction temperature, the amount of catalyst and were discussed. The results show that the activation energy of CNT-CS-Ni catalyzing reduction of nitro phenol by NaBH4 is 50.28 kJ.mol＂~, the activation enthalpy is 47.66 kJ.mol~ and entropy of activation is -99.84 J＊mol.K -t. The reaction rate constant of reduction of nitro phenol by NaBI-h is increased by an approximate linear trend with amount of CNT-CS-Ni.