A new type of supported catalyst, {PO4[WO(O2)2]4}37PSN, was synthesized by loading the peroxide phosphotungstic acid on the modified polystyrene-divinylbenzene fiber. The structures of the synthesized catalysts were characterized by FT-IR, DTA-TG, BET-BJH, respectively, and the amounts of nitrogen, phosphorus, tungsten were determined by EDS (Energy Dispersive Spectrum). The catalyst prepared was used in the epoxidation of cyciohexene with hydrogen peroxide as the oxidant. The important reaction conditions, such as the amounts of catalyst and additive catalyst used, reaction time and reaction temperature, were examined. The experimental results show that the catalyst reveals relatively high catalytic performance with 88% conversion for cyclohexene and 96.5% selectivity for cyclohexene oxide under the suitable conditions as follows: ?cyclohexene):?hydrogen peroxide)=1.75:l, /w(catalyst):w(total reactants)=l:20, m(additive):w(catalyst)=l:10, the reaction temperature of 60 "C and the reaction time of 5 h. In addition, the catalyst used repeatedly for 10 times can still possess both itsrnhigh catalytic activity and selectivity.%以改性聚苯乙烯-二乙烯苯纤维为载体,过氧磷钨酸为活性组分,合成了一种新的固载型过氧磷钨酸催化剂—{PO4[WO(O2)2]4｝3-}/PSN,通过红外、热重-差热、比表面及孔径测试等方法对其结构进行了分析,通过能谱仪测定了其中氮、磷、钨等主要元素的含量.将该催化剂应用于环己烯环氧化反应中,以过氧化氢为氧化剂,考察了催化剂用量、助剂用量、反应时间、反应温度等工艺条件.实验结果表明该催化剂对环己烯环氧化反应显示出较高的催化性能,在n(环己烯)∶n(过氧化氢)=1.75∶1,m(催化剂)∶m(原料)=1∶20,m(助剂)∶m(催化剂)=1∶10,反应温度60℃,反应时间5h的条件下,环己烯转化率可达88％,产物中环氧环己烷选择性达96.5％,重复使用十次催化性能无明显下降.
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