Metal salts with highly electronegative cations have been used to effectively catalyze the liquid-phase nitration of benzene by NO2 to nitrobenzene under solventfree conditions. Several salts including FeCl3, ZrCl4, A...Metal salts with highly electronegative cations have been used to effectively catalyze the liquid-phase nitration of benzene by NO2 to nitrobenzene under solventfree conditions. Several salts including FeCl3, ZrCl4, AlCl3, CuCl2, NiCl2, ZnCl2, MnCl2, Fe（NO3）3-9H2O, Bi （NO3）3·5H2O, Zr（NO3）4-SH2O, Cu（NO3）2.6H2O, Ni （NO3）2·6H2O, Zn（NO3）2·6H2O, Fe2（SO4）3, and CuSO4 were examined and anhydrous FeCl3 exhibited the best catalytic performance under the optimal reaction conditions. The benzene conversion and selectivity to nitrobenzene were both over 99%. In addition, it was determined that the metal counterion and the presence of water hydrates in the salt affects the catalytic activity. This method is simple and efficient and may have potential industrial application prospects.展开更多
Formic acid was used for the nitrate reduction as a reductant in the presence of Pd：Cu/γ-alumina catalysts. The surface characteristics of the bimetallic catalyst synthesized by wet impregnation were investigated by...Formic acid was used for the nitrate reduction as a reductant in the presence of Pd：Cu/γ-alumina catalysts. The surface characteristics of the bimetallic catalyst synthesized by wet impregnation were investigated by SEM, TEM-EDS. The metals were not distributed homogeneously on the surface of catalyst, although the total contents of both metals in particles agreed well with the theoretical values. Formic acid decomposition on the catalyst surface, its influence on solution pH and nitrate removal efficacy was investigated. The best removal of nitrate （50 ppm） was obtained under the condition of 0.75 g/L catalyst with Pd：Cu ratio （4：1） and two fold excess of formic acid. Formic acid decay patterns resembled those of nitrate removal, showing a linear relationship between kf （formic acid decay） and k （nitrate removal）. Negligible amount of ammonia was detected, and no nitrite was detected, possibly due to buffering effect of bicarbonate that is in situ produced by the decomposition of formic acid, and due to the sustained release of H2 gas.展开更多
基金We gratefully acknowledge the financial support for this work by the National Natural Science Foundation of China （Grant Nos. 21676226 and 21306158）, the Collaborative Innovation Center of New Chemical Technologies for Environmental Benignity and Efficient Resource Utilization, and the Project of Technological Innovation ＆ Entrepreneurship Platform for Hunan Youth （2014）.
文摘Metal salts with highly electronegative cations have been used to effectively catalyze the liquid-phase nitration of benzene by NO2 to nitrobenzene under solventfree conditions. Several salts including FeCl3, ZrCl4, AlCl3, CuCl2, NiCl2, ZnCl2, MnCl2, Fe（NO3）3-9H2O, Bi （NO3）3·5H2O, Zr（NO3）4-SH2O, Cu（NO3）2.6H2O, Ni （NO3）2·6H2O, Zn（NO3）2·6H2O, Fe2（SO4）3, and CuSO4 were examined and anhydrous FeCl3 exhibited the best catalytic performance under the optimal reaction conditions. The benzene conversion and selectivity to nitrobenzene were both over 99%. In addition, it was determined that the metal counterion and the presence of water hydrates in the salt affects the catalytic activity. This method is simple and efficient and may have potential industrial application prospects.
基金supported by the Korea Foundation for the Advancement of Science and Creativity under Project URP (2009-04-219)by (in part) Sunchon National University Research Fund in 2012
文摘Formic acid was used for the nitrate reduction as a reductant in the presence of Pd：Cu/γ-alumina catalysts. The surface characteristics of the bimetallic catalyst synthesized by wet impregnation were investigated by SEM, TEM-EDS. The metals were not distributed homogeneously on the surface of catalyst, although the total contents of both metals in particles agreed well with the theoretical values. Formic acid decomposition on the catalyst surface, its influence on solution pH and nitrate removal efficacy was investigated. The best removal of nitrate （50 ppm） was obtained under the condition of 0.75 g/L catalyst with Pd：Cu ratio （4：1） and two fold excess of formic acid. Formic acid decay patterns resembled those of nitrate removal, showing a linear relationship between kf （formic acid decay） and k （nitrate removal）. Negligible amount of ammonia was detected, and no nitrite was detected, possibly due to buffering effect of bicarbonate that is in situ produced by the decomposition of formic acid, and due to the sustained release of H2 gas.
