Design And Preparation Of A Ternary Photocatalyst TiO₂-?AC+AB? For Efficient Treatment Of Dye Wastewater

Printing and dyeing wastewater is a kind of organic wastewater in industries.It is very difficult to degrade.Traditional biological and chemical methods have limitations in practical application.In recent years,photocatalytic oxidation technology has become a new wastewater treatment technology,which has great prospect for its development.To improve photo catalytic activity of TiO₂,many modification methods had been tried.Activated carbon?AC?has rich microporous structures,its surface area is very big and it usually used to be adsorbent.In the paper we explore whether AC can improve the adsorption capacity and acetylene black?AB?can inhibit the recombination of photogenerated electron-hole pairs in the TiO₂.Nano titanium dioxide was prepared by sol-gel method.Titanium alcohol ratio,calcination temperature and calcination time were studied on the effect of photocatalytic performance in TiO₂.The experimental results showed that the best preparation condition of TiO₂ was that 3 mL butyl titanate,20 m L anhydrous ethanol,0.6 mL?2 mol/L?hydrochloric acid,1 m L deionized water,450 ? calcination temperature and 2h calcination time.The characterization of sample by XRD showed that the TiO₂ was anatase phase,the particle size of it was 13.31 nm.binary catalyst TiO₂-AC,TiO₂-AB and ternary composition catalyst TiO₂-?AC+AB?were synthesized by sol-gel method.The adsorption capacity and photo catalytic activity had been studied.Congo red and Alizarin red were used as simulative dyeing wastewaters in the paper.The experimental results showed that binary catalyst TiO₂-AC and TiO₂-AB had higher photocatalytic performance compared with nano titanium dioxide.AC and AB can adsorb Congo red,but AB does not have adsorption for Alizarin red.The removal rate was 98 % both TiO₂-3%AC and TiO₂-0.7%AB when Congo red was degraded.When Ti:AB was 1:0.01,TiO₂-1%AB showed the best photocatalytic performance,the removal rate of Alizarin red was 98 %.In the system of TiO₂-?AC+AB?,AC was used for improving the adsorption capacity and AB was used for inhibiting the recombination of photogenerated electron-hole pairs in the TiO₂.TiO₂,AC and AB showed the most obvious synergism when Ti:AC:AB was 1:0.01:0.006 in the system of TiO₂-?AC+AB?.After repeated 5 times,the removal rate of Congo red was 90 %,the photocatalytic property of ternary composition catalyst TiO₂-?1%AC+0.6%AB?was still stable.