【作者】 周海安；

【导师】 史鸿鑫；

【作者基本信息】 浙江工业大学 ， 应用化学， 2005， 硕士

【摘要】 纳米镍超微粒子作为一种新型、高效、高选择性加氢催化剂在化工催化领域有着广阔的前景。本文使用微乳液法制备粒径均匀的纳米镍金属微粒,并与Raney-Ni比较硝基苯加氢反应中的催化活性。 详细研究了微乳液体系的相行为和结构参数。相对于TritonX100和CTAB两种表面活性剂,SDS所形成的微乳液体系稳定区域大,受温度影响小。通过对SDS/C₅H₁₁OH/二甲苯/H₂O微乳液体系结构参数的研究,探讨了表面活性剂的平均聚集数、醇转移自由能变化、水核半径与含水量的关系。 选择SDS与C₅H₁₁OH的质量比为2:4的SDS/C₅H₁₁OH/二甲苯/H₂O微乳液体系,用于纳米Ni金属的制备,确定了较佳工艺。经洗涤和煅烧纯化,得到平均粒径20nm的纳米镍微粒。 纳米镍催化硝基苯加氢的活性受氢气压力、反应温度和催化剂粒径的影响。与Raney-Ni相比,在相同的反应条件下纳米镍的催化硝基苯加氢活性和最快反应速度分别为Raney-Ni的6倍和10倍。更多还原

【Abstract】 Nano-nickel was widely used as a new, high activity and high selectivity hydrogenation catalyst in chemical industry. In this article, nano-nickel particles were prepared in W/O microemulsion. The catalytic activities of Nano-Ni and Raney-Ni were compared in the reaction of nitrobenzene hydrogenation.The phase behaviors and structural parameters of microemulsion systems were studied in detail. By comparison, surfactant SDS was superior to TritonX 100 and CTAB in stable area of microemulsion system and the influence of temperature. By studying the structural parameters of SDS / C₅H₁₁OH / Xylene / H₂O microemulsion system such as n, △G_c→i^oand R_w, the relationships between the three parameters and water content were discussed.Nano-Ni was prepared in the microemulsion system of SDS / C₅H₁₁OH / Xylene / H₂O in which the mass ratio of SDS and C₅H₁₁OH was 2:4 . The optimal process parameters were selected. The Nano-Ni particles were purified by washing and calcining, and their average更多还原