| Phenolic compounds mainly come from textile and other industrial wastewater discharge, which not only pollute the environment, but also affect human health. They have the natures of carcinogenic, teratogenic, mutagenic, and affect the genetic features of organisms. The treatment methods of phenolic wastewater are mainly physical, biological, chemical, etc. Compared to physical method and biochemical method, catalytic oxidation method have the advantages of quicker degradation rate, higher removal rate, stronger oxidizing ability, sampler operation, more mature technology, also wider range of application. Though, fenton reagent method has been frequently used as a chemical technique for treating phenols, because of its characteristics of simple, strong degradation ability and so on. But fenton reagent would lose iron ions seriously, cause secondary pollution and its poor repeating utilization. Polypyrrole(PPy) is a conjugated, electric functional polymer. Its synthetic methods, electrical conductivity and stability is simple, high, good, respectively, also it has the characteristics of non-toxic and reversible redox properties. But its small density, water insoluble and organic solvent insoluble ingeneral, bad mechanical properties, that greatly limits its processing and extensive application in industrial production. In order to exert the special properties of the PPy, and conquer its deficiencies at the same time, PPy was prepared by chemical oxidation method, and ppy was loaded on nano-silica which has good biocompatibility to get polypyrrole/nano-silica(PPy/nSiO2) and copper doped state of polypyrrole/nano-silica composite materials, which were applied to in the oxidation and degradation of hydroquinone (HQ). The main contents are as following(1) Phenols and its harm were introduced simply in this paper. The treatments of wastewater containing phenols and there advantages and limitations were also discussed, including physical method, biochemical method and chemical method, etc, As well as the methods for the preparation of polypyrrole and research progress in detail. The meanings of topic and the contents of experiments were elaborated.(2) PPy/nSiO2composite was prepared by chemical oxidative polymerization of pyrrole (Py). And its molecular structure and morphology were characterized by XRD, FT-IR spectrum, SEM, XPS. This composite was used for hydroquinone (HQ) oxidation degradation. The results showed that PPy was loaded on most of the surface of nano-SiO2and evenly dispersed in nSiO2, which overcome the defects of PPy as its small density and incompletely contact with reactant. Additionally, it also enhanced the special area of PPy, as well as improved the reaction activity between PPy and HQ. The degradation mechanism of PPy/nSiO2to HQ may be the active intermediates of PPy (HPPy) make HQ degradated, and PPy/nSiO2plays a dual role of oxidant and catalyst. The degradation process was in line with the apparent first-order reaction kinetics.(3) PPy/nSiO2composite doped with Cu2+was prepared by copper nitrate solution. And its molecular structure and morphology were characterized by XRD, FT-IR, SEM, XPS. The performance of Cu2+-PPy/nSiO2composite degrading hydroquinone (HQ) was studied by means of UV-vis spectrophotometer at room temperature. The pH of the system, time and initial concentration of HQ on degradation reaction were investigated.(4) The performance of Cu2+-PPy/nSiO2composite degrading hydroquinone (HQ) was studied by means of UV-vis spectrophotometer at room temperature with H2O2as oxidizing agent. The pH of the system, time, initial concentration of HQ and the dosage of the composite on degradation reaction were investigated, and the oxidation degradation mechanism of between HQ and Cu2+-PPy/nSi02was discussed. |
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