Preliminary Study On Photocatalytic Degradation Of Phenol-containing Wastewater Through TiO₂

In this paper, phenol was choosed as the research object. The method of spectrophotometer in 4-Aminor-Antipyrine was used to analyse phenol in this study. Analysis of TiO₂ photocatalytic degradation characteristics of phenol, factors that affect photocatalytic degradation property of phenil by TiO₂ and kinetics model of photocatalytic degradation of phenil have been studied in this paper.(1) The anatase TiO₂ contained 10 percent of rutile TiO₂ show better photocatalytic performance, degradation effect of phenol is best of all with it.(2) The main factors that affect photocatalytic property of TiO₂ were phenol initial concentration, illumination, pH, reaction time and photocatalyst amount. With the rise of phenol's initial concentration, the degradation rate of phenol decreased; The UV's effect is better, with the rise of light distance or effective depth, the degradation rate of phenol decreased; The degradation rate of phenol is better in acidic solution than in alkaline solution; With the prolonging of reaction time, the degradation rate of phenol increased quickly at first and then wasn't change; With the rise of photocatalyst amount, the degradation rate of phenol increased quickly at first and then wasn't change. When the original concentration of phenol is 100mg/L and volume is 100mL, the optimal condition of photocatalyst is that photocatalyst amount is 100mg, illumination is UV, light distance is 100mm, effective depth is 10mm and reaction time is 2h, the degradation rate of phenol reached 75%.(3) Photocatalyst aid has good effect on degradation of phenol in photocatalytic reaction. Result shows that when added minim H₂O₂, the degradation rate of phenol increased 30%, and reached 85% after 1h; added Fe³⁺, Cu²⁺, the degradation rate of phenol effect increased 15%(Fe³⁺), 10%(Cu²⁺); the H₂O₂ cooperated with iron ion has markedness effect on degradation of phenol, the reaction was shortened, the degradation rate of phenol reached 95% after 80min, and all almost degraded after 100min.(4) When the phenol's initial concentration is in 30～150mg/L, kinetics research shows that the photocatalytic degradation reation can be expressed by an appearance first order equation, which also can be described by Langumuir—Hinshelwood Model. The L—H equation is(5) The titanium dioxide photocatalytic degradation has good effect on treatment of industrial phenol-containging wastewater, the degradation rate of phenol, COD and color were very high. The degradation of three industrial wastewater's phenol reached above 99%, the treatment of COD and color has reached national standard.