Catalytic Performance of CsCuHPVAsMoO Heteropolycompounds for Selective Oxidation of Isobutene

A series of CsCuHPVAsMoO heteropolycompound catalysts were prepared by combination. The catalysts were characterized by FT IR, H 2 TPR, NH 3 TPD and TG DTA. The selective oxidation of isobutene was carried out in a continuous flow fixed bed reactor. The effects of the contents of Cs, Cu and As and the calcination temperature of the catalysts on the activity and the selectivity of the catalysts were studied. The results showed that the addition of Cs is very important for increasing the catalyst selectivity and the addition of Cu and As markedly improve the activity and the selectivity of the catalysts. Among the catalysts, Cs 0.1 Cu 0.2 H x PVAs 0.2 Mo 10 O y calcined at 340 ℃ exhibits the best catalytic performance in selective oxidation of isobutene. Under the optimum reaction conditions of n ( i C = 4) ∶ n (O 2) ∶ n (N 2) =1 0∶4 17∶1 83, SV=540 h -1 and θ =340 ℃, the yield of methacrylic acid, methacrolein and acetic acid can reach 52 84%, 12 05% and 18 21% respectively, suggesting that Cs 0.1 Cu 0.2 H x PVAs 0.2 Mo 10 O y is a promising catalyst.