环己酮氨肟化及贝克曼重排反应研究

河北工业大学

硕士学位论文

环己酮氨肟化及贝克曼重排反应研究

姓名：姬亚宁

申请学位级别：硕士

专业：化学工艺

指导教师：程庆彦

20100501

河北工业大学硕士学位论文

i 环己酮氨肟化及贝克曼重排反应研究

摘要

环己酮氨肟化一步法合成己内酰胺是重要的新型绿色化学反应。柱撑蒙脱土是一种人工合成的新颖催化材料，在催化领域有较广阔的应用前景。本文研究了钛柱撑蒙脱土、硅钛柱撑蒙脱土和掺杂稀土金属的硅钛柱撑蒙脱土的制备，对其进行了物化性质表征，在环己酮氨肟化反应中测试了其催化性能；以P2O5为催化剂，使用迅速简单的微波技术，通过液相贝克曼重排法高收率的制得己内酰胺；将这两种工艺过程集成，研究环己酮氨氧化一锅合成己内酰胺的反应。

采用溶胶凝胶法制备钛柱撑剂、硅钛柱撑剂及掺杂稀土金属的硅钛柱撑剂，离子交换法制备柱撑型蒙脱土催化剂，进行了XRD、FT-IR、TG-DSC、SEM-EDX、BET等表征分析，通过环己酮氨肟化反应进行催化性能评价。结果表明，Ti:MMT为6mmol:1g，柱撑剂的OH-:H+摩尔比为3:1、Si:Ti摩尔比为1:2、水热法交联、450℃焙烧，硅钛柱撑蒙脱土的层间距由原钠基蒙脱土的0.98nm增大到1.02nm，比表面积由原钠基蒙脱土的35.9m2/g变为138.3m2/g，热稳定性较好，当温度升到900℃时，失重率为2.27%。铕掺杂的硅钛柱撑蒙脱土有较好的荧光性能。活性评价结果表明：反应时间为5h，反应温度为75℃，催化剂Eu3+掺杂硅钛柱撑蒙脱土用量为0.5g，n(环己酮):n(H2O2):n(NH3)为1.0: 1.5:2.0，环己酮肟的收率为24.93%。

以P2O5为催化剂，研究了环己酮肟液相贝克曼重排反应，发现微波辐射对此反应有促进作用，考察了重排反应中的影响因素，优化的工艺条件为：催化剂P2O5的质量分数为14%，10mL N,N-二甲基甲酰胺为反应介质，1.153g环己酮肟，微波辐射强度为280W，辐射时间5min，环己酮肟的转化率达到99.89%，己内酰胺的收率达到了95.48%、选择性为97.45%。

在环己酮氨肟化反应与贝克曼重排反应集成中，环己酮肟化反应步骤中水、环己酮和催化剂对液相贝克曼重排反应的影响较大，使得一锅法合成己内酰胺过程较为复杂。

关键词：环己酮，氨肟化，柱撑蒙脱土，P2O5，液相贝克曼重排，微波促进

环己酮氨肟化及贝克曼重排反应研究

ii

STUDY ON THE REACTION OF CYCLOHEXANONE AMMOXIDATION AND B ECKMANN REARRANGEMENT

ABSTRACT

The one-step synthesis ofε-caprolactam(CPL)from cyclohexanone ammoxidation is one of

the novel routes in green chemistry.The pillared montmorillonite is a novel synthetic catalytic material,which have application prospect in the catalytic field.In this thesis,titanium pillared montmorillonite,silicon titanium pillared montmorillonite and earth metal doped silicon-titanium pillared montmorillonite were synthesized and their physicochemical properties were characterized thoroughly,the catalytic performance for cyclohexanone ammoximation was investigated.ε-caprolactam was synthesized by microwave assisted to improve the catalytic performance of P2O5catalyst towards cyclohexanone oxime liquid phase Beckmann rearrang-ement.Then,the one-pot synthesis ofε-caprolactam from cyclohexanone ammoxidation was studied.

Titanium pillared-reagent,silicon-titanium pillared-reagent and rare metal doped silicon–titanium pillared-reagent were prepared by sol-gel method,and pillared montmorillonite catalysts were prepared by ion exchange method.The prepared pillared montmorillonite were determined by XRD,FT-IR,TG-DSC,SEM-EDX and BET.The catalytic performance of the catalysts for cyclohexanone ammoximation was investigated.The results show that when Ti: MMT ratio is6:1(mmol/g),OH-:H+for pillared-reagent molar ratio is3:1,Si:Ti molar ratio is 1:2,hydrothermal cross-linking method,calcinations temperature is450℃,the spacing of layers of silicon-titanium pillared montmorillonite increase from0.98nm of the sodium montmori-llomite to1.02nm,the specific surface area of silicon-titanium pillared montmorillonite increase from35.9m2/g of the sodium montmorillomite to138.3m2/g.The silicon-titanium pillared montmorillonite show good thermal stability,when the temperature arrives at about900℃,the weight loss is only2.27%.Eu3+doped silicon–titanium pillared montmorillonite show good fluorescence properties.The result of activity evaluation for cyclohexanone ammoximation show that when reaction time is5h,the reaction temperature is75℃,the amount of catalyst Eu3+ doped silicon–titanium pillared montmorillonite is0.5g,n(cyclohexanone):n(H2O2):n(NH3) is1.0:1.5:2.0,the yield of cyclohexanone oxime is24.93%.

The catalytic performance of P2O5catalyst towards cyclohexanone oxime liquid phase