负载型钼-钒-磷杂多酸的制备及应用

采用一种新的钼 -钒 -磷杂多酸 (HPA)的合成方法 ,利用IR、紫外 -可见光谱等说明合成的杂多酸具有keggin结构 .将其作为催化剂用于邻苯二甲酸二丁酯的合成反应中 。

化学掺杂钼钒磷杂多酸的漆酚树脂固体催化剂的制备及应用

用化学掺杂的方法,将钼钒磷杂多酸(HmPMo12-nVnO40HPA)固载于漆酚聚合物(UR-HPA)中。通过红外光谱、热重等测试手段对所制得的UR-HPA进行了表征。结果显示HPA和UR间进行了化学键合。同时以缩合反应为催化模型,考察了催化剂在缩酮反应中的催化活性,在UR-HPA催化剂存在下,环己酮乙二醇缩酮(CHGK)的得率为88.4%,催化剂重复使用15次后,CHGK得率仍有85.2%。

Trimethyl-1,4-Benzoquinone Synthesis via 2,3,6-Trimethylphenol Catalytic Oxidation by Oxygen in the Presence of Non-Keggin-Type Mo-V-Phosphoric Heteropoly Acid Solutions

In the present study, the modified （non-Keggin-type） aqueous solutions of Mo-V-phosphoric heteropoly acids HaPzMoyVx,Oh （HPA-x＇） were applied as homogeneous catalysts for the two-stage oxidation of TMP （2,3,6-trimethylphenol） by oxygen into TMQ （2,3,5-trimethyl-l,4-benzoquinone）, the latter being the key intermediate in the synthesis of vitamin E. The TMQ yield was analyzed regarding solvent type, reaction temperature, molar HPA-x ＇：TMP ratio, and the concentration of vanadium （V） in the HPA-x＇ solution. The TMQ yield was found to depend strongly on the catalyst redox potential and the rate of electron transfer. The results obtained enabled to establish the optimal reaction conditions as well as to suggest the reaction mechanism. In the target reaction, which proceeds in the two-phase system, the TMQ yield is higher than 99%. After phase separation, the catalyst is rapidly regenerated by oxygen and reused.