Study On The Preparation Of Cyclohexanol By Catalysis Hydration Of Cyclohexene

Cyclohexanol,mainly used for adipic acid and caprolactam production,is the indispensably semifinished product of polyacidamides,and is widely used as solvent for many polymers.The traditional method of cyclohexanol production is cyclohexane oxidation process,but due to the participation of oxygen,explosion is easy to occur,i.e.,it is not safe.As the success of benzene partial hydrogenation to prepare cyclohexene developed by Asahi Chemical Industry Co.,Ltd.,cyclohexanol prepared through cyclohexene is paid attention to increasingly.The key point of the technology is the design and selection of the catalyst.So this paper mainly deals with the catalyst used for the cyclohexene hydration process and the optimization of the reaction process.Firstly,the catalyst used for the hydration process was evaluated,including zeolites and ion exchange resins such as zeolites—HSSY,HUSY,Hβand HZSM-5, and ion exchange resins—Amberlyst 15 wet,Amberlyst 35 wet,Amberlyst 36 wet, CD450,CD550,CD650,ZGC107.HZSM-5 and Amberlyst 36 wet were good catalysts.Secondly,under the condition of eliminating affection of diffusion,the influences of reaction temperature,reaction pressure,reaction time,catalyst content and the feed mole ratio on cyclohexene hydration of the HZSM-5 zeolite and Amberlyst 36 wet ion exchange resin were studied.The optimal reaction conditions were as followings:as to HZSM-5,reaction time 4 hours,temperature 405K,pressure 0.75Mpa,catalyst content 20%(w/w),feed mole ratio n(C₆H₁₀):n(H₂O)=1:14;for Amberlyst 36 wet,temperature 413K,pressure 0.75MPa,reaction time 4 hours, catalyst content 20%(w/w),feed mole ratio n(C₆H₁₀):n(H₂O)=1:14.Under this circumstance,the cyclohexene conversion,cyclohexanol selectivity,cyclohexanol yeild were 9.84%,99.71%,9.73%respectively to HZSM-5 zeolite catalyst,and 12.38%,99.86%,12.36%respectively to Amberlyst 36 wet catalyst.At the same time, the stability of HZSM-5 zeolite and Amberlyst 36 wet ion exchange resin was studied. The results showed that the yield of cyclohexanol was nearly invariable after 5 times for the same catalyst.The toxic HZSM-5 zeolite was regenerated in muffle oven at 500℃after H₂O₂ processing.At last,cyclohexene hydration kinetics was explored primarily and its model was obtained.