Photocatalytic treatment of stained wastewater coming from handicraft factories. A case study at the pilot plant level

Abstract

UV/H2 O2 process and TiO2-based photocatalysis were studied in the present work. The effectiveness of these methods was tested in the treatment of effluents taken from handicraft factories. Microorganisms, dyes, and different organic pollutants were detected in the industrial effluents. The experimental procedure for the wastewater treatment was carried out in a patented sunlight reactor on a pilot plant scale. From this study, UV/H2 O2 was found to be the best treatment for dye elimination. The optimal peroxide dosage for the degradation of dyes and the elimination of bacteria was 0.07 M. In this case, 70.80% of discoloration was achieved after 7 h of sunlight exposure, under an average sunlight intensity of 3.42 W/m2 . The photocatalytic treatment based on TiO2 achieved the highest elimination of coliform bacteria and the lowest TOC value; however, the presence of this material in the reactor had a detrimental effect on the overall elimination of dyes. A combination of both UV/H2 O2 and TiO2 treatments significantly improves the dyes discoloration, the elimination of bacteria, and the organic compounds degradation. Some of the results of this study were presented at the 4th Congreso Colombiano de Procesos Avanzados de Oxidación, 4CCPAOx.