改性VPO催化剂及其环己烷液相氧化反应性能.pdfVIP

学兔兔 化 工 进 展 ·1474· CHEMICAL INDUSTRY AND ENGINEERING PROGRESS 2010年第29卷第8期 改性VPO催化剂及其环己烷液相氧化反应性能 仇念海，史运国，宋 华 (东北石油大学化学化工院，黑龙江 大庆163318) 摘 要：采用共沉淀法制备了铋改性钒磷氧催化剂，并用x射线衍射 (XRD)、FTIR、SEM等技术对催化剂进 行了表征。以环己烷为原料，H，O 为氧化剂，铋改性的钒磷氧化物为催化剂，研究了氧化合成环己醇和环己酮 反应，研究了Bi／V比率、P，V比率、溶剂和反应温度等因素对其反应性能的影响。结果表明，Bi／V比率提高时， 环己烷转化率，尤其是环己酮的选择性明显提高。P／V比对改性催化剂活性和结构影响较大，P的加入破坏了 V，O 的晶型结构，形成大量磷酸盐物种。在Bi／V摩尔比为0．1、P／V摩尔比为O．92、丙酮为溶剂、65℃的反应 条件下，反应8 h，环己烷转化率为81．4％，环己酮和环己醇的收率分别为58I2％和23-2％。 关键词：环己烷；液相氧化；钒磷氧化物；过氧化氢；铋助剂 中图分类号：0 643 文献标识码：A 文章编号：1000—6613(2010)08—1474—06 Modified-VPO catalyst for liquid-phase selective oxidation of cyelohexane OiU Nianhai，SHI Yunguo，SONG Hua (Collge ofChemistry and Chemical Engineering，Northeast Petroleum University，Daqing 163318，Heilongjiang，China) Abstract： Vanadium—phosphorous oxide catalysts modified with bismuth were prepared by coprecipitation and characterized by X—ray diffraction(XRD)，FTIR and SEM．Catalytic behavior of the prepared Bi·-modified vanadium--phosphorous oxide catalysts for selective oxidation of cyclohexane with hydrogen peroxide as the oxidant was investigated wim variations in Bi／V and P／V molar ratios， solvent and temperature． Results showed that cyclohexane conversion and selectivity for cyclohexanone were obviously improved with the increase in B molar ratio The molar ratio showed a great influence on catalyst structure and performance．The addition of P could significantely destroy the crystal structure of V205 by producing some phosphates．Under optimized conditions， (Bi)／n(V)=O．1，n(P)／n(V)：0．92，acetone as the solvent at 65℃