Preparation of Complex Oxide WO_3-SnO_2 for Catalytic Synthesis of Adipic Acid

Complex oxide WO3-SnO2was prepared and employed as the catalyst for the synthesis of adipic acid from cyclohexanone with 30% hydrogen peroxide as oxidant.The appropriate preparing conditions were n(WO3)∶n(SnO2)=1∶2and calcinating at 500℃for 3h.The catalyst was characterized by IR technique.The effects of various factors such as catalyst dosage,hydrogen peroxide dosage,reaction time and reusability of the catalyst were investigated.The results indicated that the optimal reaction conditions were as follows:100mmol cyclohexanone,50mL 30% H2O2and 1.25g WO3-SnO2catalyst.The yield of adipic acid could reach 82.5%.Catalytic activity of WO3-SnO2complex oxide was superior to WO3.The catalytic activity of WO3-SnO2/La was less than WO3-SnO2,but its reusability was better than WO3-SnO2.