Synthesis Of Adipic Acid Catalyzed By Phosphotungstic Acid Supported On Polymers

Adipic acid is an important organic intermediate, but oxidation method of nitric acid has the shortcomings of environmental pollution and serious equipment corrosion.Much attention has been paid for its green synthesis process. In thisthesis,30%hydrogen peroxide and polymer-surpported phosphotungstic acid (HPW)were used as oxidant and catalyst for synthesis of adipic acid. Main work includes:1. P(NIPAM-AM-DMDAAC) was prepared through ion-exchange betweenquaternary ammonium groups of temperature-sensitive cationic hydrogel and HPW.The resulted compound catalyst was characterized by FT-IR, TG-DSC, SEM andEDX. Most of catalyst was found to distribute in the surface of the hydrogel, and onlyfew was in the inner surface. The effect of some factors, including temperature, time,catalyst dose and etal, were investigated on the yield of adipic acid. The result showedthat the yield reached56%.2. PDMDAAC/HPW and PQ-11/HPW were prepared by using linear cationicpolymer with phosphotungstic acid. FT-IR, TG-DSC, SEM and TEM were used todetermine their composition and structure. Catalytic activity in the synthesis of adipicacid by catalytic oxidation of cyclohexanone was investigated. It was concluded thatthe catalyst showed better catalytic activity than P(NIPAM-AM-DMDAAC)/HPW,and the yield of adipic acid can reach65%. Besides, the one composing of thecationic polymer with higher charge density benefited the yield of adipic acid.3. P (NIPAM-MTC)/HPW was prepared through self-assembly betweenquaternary ammonium groups of synthetic temperature-sensitive cationic linearpolymer and HPW. The catalyst was characterized by FT-IR, TG-DSC, SEM andTEM to determine its composition and structure. Temperature sensitivity of thecatalyst was discussed. The effect of some factors, including temperature, time,catalyst dose and etal, were investigated on the yield of adipic acid. The result showedthat the yield reached66%. The yield of adipic acid by oxidation of cyclohexene at low temperature was higher than the yield of adipic acid by oxidation ofcyclohexanone under high temperature.The catalyst in this work did not give good yield of adipic aicd, but it provided apotential possibility for the green synthesis of adipic acid. Also it provided a referencefor other two phase organic reaction.