Degradation Of Chlorophenol Electrochemical Study Of The Influence Factors

In this dissertation, with the simulation contaminant of p-chlorophenol, a study has been made of the electrochemical Degradability of p-chlorophenol. As organic chemical materials, chlorophenols compounds are applied in the fields of fine chemistry, pesticide, dyestuff, paper making, medicine, wood preservative, bactericide, etc. At the same time, being highly toxic, carcinogenesis, teratogenesis and mutagenesis, those compounds are of slow degradation.In three-electrode electrolysis bath, by the use of Linear Sweep Voltammetry, a research has been made into the effectiveness of three kinds of anodes (made of PbO₂/Ti, or graphite, or platinum ) on the electrochemical oxidative degradation of p-chlorophenol. And in the above-mentioned three systems of anode electroanalysis, the curves of Linear Sweep Voltammetry of p-chlorophenol has shown that the current density increases with the rise of electrode potential, and most markedly does so with anode of PbO₂/Ti. This has therefore proven that anode of PbO₂/Ti is capable of the electrochemical-photocatalytic-oxidative degradation of p-chlorophenol.In the electroanalysis system with PbO₂/Ti as anode and Ti plate as cathode, by the adoption of constant current electrolysis, an analysis has been made of the effects of pH,such anions as Cl- and ClO-,cations like Mn²⁺and Ni²⁺, on the degree and process of the electrochemical degradation of p-chlorophenol. In addition, with the application of external standard method, High Performance Liquid Chromatography(HPLC)is utilized in the inspection of p-chlorophenol and its intermediate products. Experiments have shown that on the PbO₂/Ti electrodes, p-chlorophenol, after direct electro-oxidation, produces hydroquinone, catechol, p-benzoquinone, Maleic acid, and CO₂(final product).In the simulated waste water, Cl^- and ClO^- help the degradation of p-chlorophenol: degradation rate is rapidest, with solution containing 1.25 mmol·L^-1Cl^-; the adding of 1.0 mmol·L^-1Mn²⁺ and 0.5 mmol·L^-1Ni²⁺into the the simulated waste water facilitates the eIectro-oxidation of p-chlorophenol to varying degrees, In particular, the adding of Mn²⁺ increases the conversion rate of p-chlorophenol and its removal rate. Compared with the direct eIectro-oxidation of p-chlorophenol, the time limit for the complete degradation of p-chlorophenol is shortened from three hours to two hours. The above work has provided a new method for the cleaning of industrial wastewater containing phenol, and a bright prospective for further study.