五氯酚催化湿式氧化降解反应及动力学研究

THE DEGRADATION REACTION AND KINETIC OF PENTACHLOROPHENOL IN CATALYTIC WET AIR OXIDATION

以高温老化法制备了ZrO2载体,其比表面积为251.6 m.2g-1,采用等体积浸渍法制备了Ru/ZrO2催化剂,用于催化湿式氧化法处理五氯酚.研究了反应温度、氧气分压、PCP初始浓度及时间对PCP转化率的影响.研究结果表明,提高反应温度、增加氧气分压、减小PCP初始浓度及延长反应时间均可提高五氯酚的转化率.在C0PCP=2000 mg.L-1、180℃、1.1 MPa氧分压反应条件下,90 min后五氯酚降解率可达99%.由于吸电子基团—Cl导致苯环不易被打开,因此COD转化率只有46.2%.对五氯酚进行动力学研究,结果表明,五氯酚催化湿式氧化反应符合准一级动力学模型,阿仑尼乌斯活化能为96.98 kJ.mol-1.

ZrO2 support with a specific surface area of 251.6 m2·g-1 was prepared by high temperature aging method.Ru/ZrO2 catalyst was prepared by incipient impregnation,and was applied in the catalytic wet air oxidation of pentachlorophenol.The effect of reaction temperature,oxygen partial pressure,the initial concentration of PCP and reaction time on the degradation of PCP was studied.The results showed that PCP conversion was increased by increasing the reaction temperature,oxygen partial pressure and reaction time and reducing the initial concentration of PCP.Under C0PCP=2000 mg·L-1,180 ℃,1.1 MPa O2 reaction conditions,the conversion of PCP reached 99% after 90 minutes reaction time.Because the benzene ring was difficult to be opened due to the withdrawing electron group—Cl,COD removal was only 46.2%.The kinetics of PCP in CWAO was studied.The results showed that the catalytic wet air oxidation reaction of PCP follows pseudo-first order kinetic model,and the Arrhenius activation energy was 96.98 kJ·mol-1.