Study On The Preparation Characterization Of Activated Carbon Supported TiO₂ Composite And The Photocatalytic Degradation Of Reactive Yellow Dye Wastewater

Dye wastewater is one of the main sources of environmental pollution, which is characterized with complication of organic components, more difficulty reduced substances, high concentration and more difficulty degraded. Photocatalytic technology is an effective way to solve the environmental problem. Titanium dioxide as a catalyst is widely used in the field of sewage wastewater treatment and organic matter degradation for its high photocatalytic activity, `good chemical stability, low toxicity and cheapness. However, the spectral range that titanium dioxide can use is very narrow, meanwhile, it is easy to reunite and difficulty to be separated and reuse, which greatly increase the processing cost. Hence, researching the new titanium dioxide based photocatalyst with high photocatalytic activity and evaluating its photodegradation efficiency of dye wastewater have been got more and more attention. It has very important significance for not only it can reduce the pollution of the organic matter, but also it can ensure the safety of human life.On the basis of the above background, the paper adopted sol-gel method to prepare the composite photocatalyst of well photocatalytic property, meanwhile which was characterized by some methods. The composite photocatalyst was applied to the study of dye wastewater treatment, in which reactive yellow dye was selected as a model compound. The results showed as follows:Firstly, coconut shell activated carbon was adopted as supports in the paper, TiO2/activated carbon(AC) composite photocatalysts have been prepared by sol-gel method. Morphology, physiochemical properties, surface functional groups, value and optical properties of Ti O2/AC were determined by methods of SEM, XRD, FT-IR, TG/DSC, UV-Vis, XPS. The results indicated that the composite photocatalyst prepared by sol-gel method had high photocatalytic activity. TiO2 particles were located on coconut shell activated carbon surface evenly. The photocatalytic activity of the composite photocatalyst was affected by calcination temperature, and the anatase crystal of TiO2 developed with increasing calcination temperature. The characteristic adsorption of the composite photocatalyst increased obviously compared with pure titanium dioxide.Secondly, the composite photocatalyst was applied to the study of dye wastewater treatment in the paper, in which reactive yellow dye was selected as a model compound. The effect of the dosage of the composite photocatalyst, the p H value of the dye wastewater, the initial concentration of dyes and so on were also studied in the paper to evaluate the photocatalytic activity of the composite photocatalyst. The results showed that there is a synergistic effect between titanium dioxide and activated carbon in this system, which has high photocatalytic activity. Within a certain range, the degradation ratios of the XRG increased with increasing the dosage of Ti O2/AC. Increasing the photocatalyst dosage beyond the optimum value(2.0g/L) had negative effect on the degradation efficiency of XRG. Acid condition is helpful to photodegradation of XRG. With the increase of XRG initial concentration, the degradation rate gradually decreased. The influence of hydrogen peroxide to light degradation effect has a dual role, while increasing the ionic strength is in favor of photodegradation of XRG.