摘要
采用分步酸化-分步加料及离子交换-冷冻法合成出含镓、锆和钨的取代型杂多酸H5[Ga(H2O)ZrW11O39].14H2O。给出了合成反应的原料配比及pH值。通过元素分析(ICP)、红外光谱、紫外光谱和X-射线粉末衍射等手段对其进行了表征。在此基础上,研究了它的导电和催化酯化反应性能。在室温(16℃)下,取代型杂多酸H5[Ga(H2O)ZrW11O39].14H2O的质子电导率为8.76×10-4S.cm-1,是一新型固体高质子导体。通过测定不同温度下的电导率,得到H5[Ga(H2O)ZrW11O39].14H2O的活化能是21.20kJ/mol。该取代型杂多酸催化剂催化酯化反应效果好且可多次重复使用。
The substituted heteropoly acid H5[Ga （H2O）ZrW11O39] · 14H2O
was synthesized by the stepwise acidification and the stepwise addition of solutions of the component elements as well as the ion exchanging-cooling method. The optimal proportion of the component compounds and the pH of the synthesis reaction are given. The product was characterized by means of inductively coupled plasma （ICP）, IR, UV, X-ray diffraction and thermal analysis. The IR, UV and XRD indicate that H5[Ga （H2O）ZrW11O39] · 14H2O
possesses the Keggin structure. The results of AC impedance measurement show that its proton conductivity is 8.76 ×10^-4 S · cm^-1 at room temperature （16 ℃） and the activation energy for proton conduction is 21.20 kJ/mol. The esterification of carboxylic acid with alcohol catalyzed by substituted heteropoly acid H5[Ga （H2O）ZrW11O39] · 14H2O
was reported. The results show that the reaction rate is faster than traditional catalyst, the conversion of acid is high and the process is simple. The regeneration of this catalyst is easily, and can be used repeatedly.
出处
《渤海大学学报（自然科学版）》
CAS
2007年第2期102-107,共6页
Journal of Bohai University:Natural Science Edition
基金
国家自然科学基金资助项目(No:20271045)
NSFC-RFBR基金资助项目(No:20511120009)
关键词
取代型杂多酸
质子电导率
催化
酯化
substituted heteropoly acid
proton conductivity
catalysis
esterification
