Department of Chemistry, Liaocheng University, Liaocheng 252059, China.
J Hazard Mater. 2010 Jun 15;178(1-3):404-8. doi: 10.1016/j.jhazmat.2010.01.095. Epub 2010 Jan 25.
A mild and clean liquid nitration of benzene with 65% nitric acid as nitrating agent over silica supported ammonium salt of 12-molybdophosphoric acid catalysts has been investigated. These catalysts with different loadings were prepared by sol-gel method and characterized by X-ray diffraction (XRD) and FTIR spectra. The acidity of these catalysts was measured by the potentiometric titration method. The XRD and IR analysis revealed that supported catalysts possess the Keggin structure which is similar to 12-molybdophosphoric acid. And it can be found that the supported catalysts had high nitration reaction catalytic activity and selectivity over nitrobenzene. The effects of various parameters such as nitric acid/benzene volume ratio, temperature and time of reaction have also been systematically studied.
以 65%硝酸为硝化剂，在负载于硅的磷钼酸铵盐催化剂上温和、清洁地硝化苯。通过溶胶-凝胶法制备了不同负载量的催化剂，并通过 X 射线衍射（XRD）和傅里叶变换红外光谱（FTIR）进行了表征。通过电位滴定法测量了这些催化剂的酸度。XRD 和 IR 分析表明，负载催化剂具有类似于磷钼酸的 Keggin 结构。可以发现，负载催化剂对硝基苯的硝化反应具有很高的催化活性和选择性。还系统研究了各种参数的影响，如硝酸/苯的体积比、反应温度和时间。
