Catalytic Wet Peroxide Oxidation For The Degradation Of Quinoline

Quinoline is one of typical refractory nitrogenous heterocyclic compounds,which is widely present in coal processing waste water. The research of quinolinedegradation can provide the basis for the removal of waste water containingheterocyclic compounds, and also can provide new ideas and new methods to theadvanced treatment of coal chemical industry wastewater. Catalytic Wet PeroxideOxidation, using H2O2as oxidant, have the advantages of high reaction rate andmineralization rate. This technology can be carried out at low temperature andpressure, which overcomes the disadvantages of conventional wet oxidation whichmust be carried out at high temperature and pressure and save a lot of high-pressurepower equipment. In this study, the establishment of Catalytic Wet PeroxideOxidation system and its application in quinoline degradation were investigated.Copper and iron oxide catalyst(CuO-FeOx/γ-Al2O3) was prepared by wetimpregnation, and the effects of the ratio and loading of catalyst active component,calcination temperature on catalytic activity were investigated to determine theoptimal preparation conditions. The catalyst was characterized by BET, SEM, XRD.The results showed that the optimal preparation process of catalyst was the ratio ofCu to Fe4:1, and the loading amount of active component about2.5wt%, and thecalcination temperature of300℃. The characterization results shows that the CuOof catalyst on the support were highly dispersed, and Fe component existed in theform of Fe3O4.Compared to the carrier, the surface area, pore volume and porediameter were smaller.Static and dynamic Catalytic Wet Peroxide Oxidation systems were establishedsystem, and were used to quinoline degradation. The degradation performance andthe factors of two systems were investigated. It revealed that Catalytic Wet PeroxideOxidation had good removal efficiency for quinoline. In the static system, acomplete quinoline conversion and88.34%total organic carbon (TOC) removalwere achieved in60min with the initial pH of7and the dose of29.15mmol/L ofH2O2and4g/L of catalyst at80℃. In the dynamic experiments, the averageremoval of TOC and quinoline in8h were76.25%and96.77%with the initialquinoline concentration of50mg/L, the dose of14.58mmol/L of H2O2and3g ofcatalyst and the HRT of60min.The kinetic of H2O2decomposition and quinoline degradation in Catalytic WetPeroxide Oxidation system were analyzed, and the role of·OH and degradationpathways of quinoline were analyzed. The results showed that the kinetics ofquinoline degradation and H2O2decomposition in Catalytic Wet Peroxide Oxidation followed pseudo-first-order kinetics;·OH oxidation played a dominant role inquinoline degradation in Catalytic Wet Peroxide Oxidation system, and its averageproduction rate was1.69×10-6mmol/L·min. Under neutral and acidic conditions,quinoline degradation in Catalytic Wet Peroxide Oxidation system followeddifferent paths, and generated pyridine-based or benzene-based intermediateproducts.