Combination of TiO2 microreactor and electroflotation for organic pollutant removal from textile dyeing industry wastewater

Photocatalytic degradation techniques have been widely used for the treatment of high organic content wastewater. The use of TiO2 photocatalytic activity combined with electroflotation process to treat a wastewater is still very rare and needs to be understood. This study proposed the UV/TiO2/Electroflotation process as a new method for the treatment of textile dyeing industry wastewater. The performance of UV/TiO2/Electroflotation microreactor system to remove the chemical oxygen demand (COD) was compared with that of other microreactor systems for the experiments conducted at different hydraulic retention times (HRTs) of 13, 30 and 60 min. The results showed that the COD removal efficiency of Florescent microreactor is lower than that of Florescent/TiO2 microreactor and then is lower than that of UV microreactor and then is lower than that of UV/TiO2 microreactor and then is lower than that of UV/TiO2/Electroflotation microreactor. Three microreactor systems of UV, UV/TiO2 and UV/TiO2/Electroflotation with their HRT of 60 min are capable of removing more than 90% of COD from the wastewater containing dyes. The efficiencies of COD removal by the UV/TiO2/Electroflotation microreactor are approximately 25% higher than those by the UV/TiO2 microreactor and are more than 81% higher than those by the UV microreactor, using the HRTs of 15 and 30 min. The use of UV/TiO2/Electroflotation process could be useful for the treatment of high organic content wastewater to contribute to advanced wastewater technology needed in the future. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University.