Undecatungstocobaltoruthenic polyoxometallic acid H7[Ru（H2O）CoW11O39] 22H2O was synthesized by the stepwise acidification and the stepwise addition of solutions of the component elements as well as the ion ex changi...Undecatungstocobaltoruthenic polyoxometallic acid H7[Ru（H2O）CoW11O39] 22H2O was synthesized by the stepwise acidification and the stepwise addition of solutions of the component elements as well as the ion ex changing-cooling method. The optimal proportion of the component compound and the pH of the synthesis reaction were given. The product was characterized by means of inductively coupled plasma（ICP）, IR, UV and thermal analy sis. The IR and UV results indicate that H7[Ru（H2O）CoW11O39] 22H2O possesses the Keggin structure. The results of AC impedance measurement show that its proton conductivity is 2.30×10-3 S/cm at room temperature（295 K） and a relative humidity of 75%.展开更多
The catalytic performance of Cs-substituted phosphomolybdic salts was studied for selective oxidation of isobutane. The results of activity tests revealed that 360 °C was the optimal reaction temperature. It was ...The catalytic performance of Cs-substituted phosphomolybdic salts was studied for selective oxidation of isobutane. The results of activity tests revealed that 360 °C was the optimal reaction temperature. It was demonstrated that oxidizing sites not only took dominating part in the activation of isobutane, but also influenced the product distribution. Besides, appropriate Cs addition led to moderate acidity of catalysts, favoring the selectivity to desired products. Furthermore, to obtain partially reduced catalysts, different calcination atmospheres were investigated and certain proportion of Mo^（5＋） produced during calcination was crucial for the redox reaction. The catalyst calcined in N2 showed the highest yield of MAA（7.0%）. Fe-substitution enhanced the activity of catalysts by rapid reoxidation of Mo^（5＋）.展开更多
基金Supported by the National Natural Science Foundation of China(No.21071124)the Foundation of Jiangxi Education De-parment, China(No.GJJ09310)the Foundation of State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, China(No.2010-16)
文摘Undecatungstocobaltoruthenic polyoxometallic acid H7[Ru（H2O）CoW11O39] 22H2O was synthesized by the stepwise acidification and the stepwise addition of solutions of the component elements as well as the ion ex changing-cooling method. The optimal proportion of the component compound and the pH of the synthesis reaction were given. The product was characterized by means of inductively coupled plasma（ICP）, IR, UV and thermal analy sis. The IR and UV results indicate that H7[Ru（H2O）CoW11O39] 22H2O possesses the Keggin structure. The results of AC impedance measurement show that its proton conductivity is 2.30×10-3 S/cm at room temperature（295 K） and a relative humidity of 75%.
基金supported by the National Natural Science Foundation of China(No.U1362201)the National 973 Program of China(No.2012CB215006)
文摘The catalytic performance of Cs-substituted phosphomolybdic salts was studied for selective oxidation of isobutane. The results of activity tests revealed that 360 °C was the optimal reaction temperature. It was demonstrated that oxidizing sites not only took dominating part in the activation of isobutane, but also influenced the product distribution. Besides, appropriate Cs addition led to moderate acidity of catalysts, favoring the selectivity to desired products. Furthermore, to obtain partially reduced catalysts, different calcination atmospheres were investigated and certain proportion of Mo^（5＋） produced during calcination was crucial for the redox reaction. The catalyst calcined in N2 showed the highest yield of MAA（7.0%）. Fe-substitution enhanced the activity of catalysts by rapid reoxidation of Mo^（5＋）.
