Research On Synthesis Of Acetophenone By Liquid-phase Catalyzed Oxidation Of Ethylbenzene

In this text, the craft route of acetophenone synthesis is studied under atmospheric pressure, which taked ethylbenzene as material, oxygen and 30% hydrogen peroxide as green oxidant respectively. The effect of solvent kind, catalyst kind and amount, assistant-catalyst kind, reaction temperature, oxidant amount and reaction time were investigated. The optimal reaction conditions were also involved.When use oxygen as oxidant, the reaction under two kind of crafts conditions were studied separately, which taked cobalt acetate and manganese sulfate as catalyst respectively to synthesize acetophenone from ethylbenzene. (1) Cobalt acetate as catalyst, the most optimal conditions under atmospheric pressure as follows: glacial acetic acid was 20mL, ethylbenzene was 5mL, Co(AC)2 was 4.2%, Br/Co=2.5, oxygen flow rate was 100mL/min , temperature of 80℃, time of 4 h, the conversion rate of ethylbenzene and the yield of acetophenone reached 99.94% and 98.49%, respectively. (2) Manganese sulfate as catalyst, the most optimal conditions under atmospheric pressure as follows: ethylbenzene was 5mL, MnSO4 was 4.9%, Br/Mn=2.0, glacial acetic acid was 10mL, oxygen flow rate was 100mL/min , temperature of 90℃, time of 4h, the conversion rate of ethylbenzene and the yield of acetophenone reached 72.36% and 59.57%, respectively.When use 30% hydrogen peroxide as oxidant, the reaction which taked cobalt acetate as catalyst to synthesize acetophenone from ethylbenzene was studied. the most optimal conditions as follows: glacial acetic acid dosage 10mL, ethylbenzene was 1mL, Co(AC)2 was 11.11%, Br/Co=1.67, n(H2O2)/n(ethylbenzene)=1.2, temperature of 80℃, time of 4h, the conversion of ethylbenzene and the yield of acetophenone is 83.74% and 82.52% respectively.The craft route of synthesis of acetophenone by Liquid-phase oxidation of ethylbenzene that was studied in this text has many advantages such as environment-friendly, conditions moderately and lowest costing etc. This work opened up a new way that can be followed by green synthesis of other organic compounds and has a certain reference value.