The Photocatalytic Oxidation Treatment Of Organic Wastewater

Treating organic wastewater is an important task with practical value. On the basis of surveying photocatalytic oxidation technology and organic wastewater controlling approaches inside and outside country, organic wastewater treated by photocatalytic oxidation technology was studied systematically in this paper. The study showed that the technology was in possession of the prominent virtues, such as high treatment efficiency, simple processing equipment, operation conditions controlled easily, organic pollutants degraded non-selectively, no secondary pollution, etc. So it can provide new thoughts and pathways for industrialization treatment of organic wastewater and will be endowed with extensive application prospect in the organic wastewater treatment. The main contents of experiment were as follows:Using phenol as objective pollutant in screening photocatalyst test, photocatalytic activity of catalyst of titanium dioxide, zirconium oxide and a few metal composite oxides was analyzed and reviewed respectively. The results indicated that the photocatalytic activity of the anatase Ti02 was best when compared to their photodegradation effect for phenol.Phenol and methyl orange were selected as representative organic pollutants to simulate organic wastewater which was treated by photocatalytic oxidation using the anatase Ti02 as photocatalyst. Factors affecting photocatalytic oxidation reaction were studied in details ,such as catalyst amount, intensity and time of UV irradiation,intial concentration of wastewater, pH value and adding concentration of H202,etc.the approaches to improve photocatalyst activity of T02 were also investigated from the temperature and time of heat treatment, preparation of ultrafine particles and adulteration of transition metal, and catalyst prepared were characterized by X-ray diffraction(XRD).The above-described influence factors were further studied in treating dyeing and printing wastewater by photocatalytic oxidation, and four factors affecting photodegradation effect obviously were selected to proceed L16(44) orthogonal experiments on the basis of mono-factor test. The optimization of printing and dyeing wastewater photocatalysis were determined to be: UV irradiation time:9Omin~amount ofTi02:6g/L;initial pH:5;adding concentration of H202: I 8OmgfL. 300W high-pressure mercury vapour lamp. Photocatalytic oxidation technology was applied to tre2.t practical dyeing and printing wastewater for the first time and the advanced research can provide theories and test reference for deep-going study and far-ranging application of the method afterwards.The kinetics of photocatalytic oxidation reaction for phenol solution was studied in TiC)2 catalyst suspension phase, the results showed that the reaction was first-order and the velocity of reaction was coincident with multiphase catalytic kinetic equation:Langmuir ?Hinshelwood equation,In addition, the mechanism of photocatalytic oxidation technology degrading organic pollutants was discussed in details.