碳材料催化硝基苯还原反应

本文对碳材料(主要是碳纳米管)催化硝基苯的还原反应进行了系统研究.通过热重分析、程序升温脱附、透射电子显微镜、物理吸附以及拉曼光谱等表征,发现碳材料表面的含氧官能团在反应中起着重要的作用,而比表面、孔结构、形貌、结构缺陷以及可能存在的铁杂质对反应没有显著影响.羰基的作用非常重要,但是羧基和酸酐对反应不利.除此之外,材料的π电子体系也很关键,因为它可以传递电子,并且利于硝基苯的吸附.硝基苯还原按照直接路径进行,反应过程中生成的中间体亚硝基苯可以迅速转化为苯胺.

Reduction of nitrobenzene catalyzed by carbon materials

The reduction of nitrobenzene catalyzed by different carbon materials (mainly carbon nanotubes) was studied. TGA, TPD, TEM, N₂ adsorption-desorption, and Raman spectroscopy were used to show that it was oxygenated groups that gave catalytic activity, while the surface area, pore structure, morphology, structural defects and Fe impurities in the catalysts did not have a significant influence on the activity. The carbonyl group played an important role, but the carboxylic group and anhydride adversely affected the reaction. The conjugated π system, which was necessary for electron transfer and nitrobenzene adsorption, was another critical factor. The reaction proceeded through the direct route in which the intermediate nitrosobenzene was converted directly to aniline quickly.