摘要
采用室温固相反应法合成出H3 CoPMo1 0 V2 O40 ·7H2 O纳米催化剂,用元素分析、IR、XRD、TEM等手段确定其组成、结构和性能,同时考察了其用于苯 过氧化氢直接羟化合成苯酚反应的催化活性和机理。结果表明,产物仍保持杂多阴离子的Keggin结构,晶粒尺寸约为3 4nm ,比表面积为1 3 6m2 ·g-1 ,在催化苯羟基化的反应中,活性中心是钒的过氧化物,苯酚收率>5 0 %,选择性>98%。
H_3CoPMo_ 10V_2O_ 40·7H_2O nanocatalyst were synthesized by solid-state reaction at room temperature. Its structure, particle size and appearance were characterized with elemental analysis, IR, UV, XRD and BET techniques. The catalytic activity and mechanism of the nano heteropoly compound catalyst in hydroxylation of benzene to phenol with H_2O_2 were studied. The results show that H_3CoPMo_ 10V_2O_ 40·7H_2O nanocatalyst prepared exhibits Keggin structure, the surface area is 136m2·g -1,the mean grain size is of the value of 34nm, the yield of phenol was over 50% and the selectivity for phenol was over 98% under the optimum conditions,which were H_2O_2/C_6H_6 molar ratios 1 5, C_6H_6/catalyst (mass ratios) 25, reaction time 2h, temperature 70℃. The active centre is heteropoly superoxide of the vanadium in the hydroxylation of benzene to phenol.
出处
《化学通报》
CAS
CSCD
北大核心
2005年第5期385-389,共5页
Chemistry
基金
国家自然科学基金 (2 0 2 6 1 0 0 3)
湛江师范学院科学研究资助项目