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以氟碳表面活性剂(FC4)和Pluronic F127在酸性乙醇溶液中形成的胶束作为模板制备具有明显的介孔孔道结构的聚合物(RF),然后以400 oC碳化后的材料(C-400)为载体,采用浸渍法负载Pt制备得到催化剂Pt/C-400。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、N_2吸附-脱附对载体和催化剂的结构进行表征,并采用油-水双相体系对其亲疏水性测试。研究表明,制备的Pt/C-400金属颗粒分散均匀,孔径尺寸均一,介孔孔道结构明显,具有一定的表面两亲性。该催化剂在硝基苯催化加氢生成对氨基苯酚反应中,硝基苯的转化率和对氨基苯酚的选择性可分别达到94%和76%,中间体苯基羟胺(PHA)的选择性明显高于负载量为5%的商业化Pt/C催化剂,表明两亲性表面催化剂有助于中间体从活性位点的脱附,在一定程度上降低了反应传质阻力,从而提高了反应选择性。
The micelles formed by the fluorocarbon surfactant (FC4) and Pluronic F127 in acidic ethanol solution were used as templates to prepare polymers with obvious mesopore structure (RF). The carbonized materials (C-400 ) As a carrier, prepared by impregnation Pt loading catalyst prepared Pt / C-400. The structure of the support and the catalyst were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption-desorption. The hydropathicity was tested by oil-water biphasic system. The results show that the prepared Pt / C-400 metal particles are uniformly dispersed, the pore size is uniform, the pore structure of the mesopore is obvious and the amphiphilicity of the surface is certain. In the reaction of nitrobenzene to p-aminophenol, the conversion of nitrobenzene and selectivity to p-aminophenol can reach 94% and 76%, respectively. The selectivity of the intermediate phenylhydroxylamine (PHA) is obvious Higher than 5% loading of commercial Pt / C catalyst, indicating that the amphiphilic surface catalyst helps the desorption of intermediates from the active site, to a certain extent, reduce the resistance of the mass transfer, thereby enhancing the reaction options Sex.