Photo degradation of carbon pollution and violet reactive dye from textile effluent in Antananarivo Madagascar

Résumé

This work is focused on the evaluation of organic matter and Violet reactive dye RV5 conveyed by textile effluents of Antananarivo – Madagascar and their photo degradation. The purpose of this study is to determine the nature of textile wastewater and pollutant degradation speed when they are exposed to light. The pH, electrical conductivity (CE), dissolve salt rate (TDS) and Chemical Oxygen Demand (DCO) have been considered to characterize effluents. Absorption spectrums, from 400 nm to 700 nm, of RV5 dye and liquid effluent have been compared in order to identify dye’s presence in effluent. The evolution of Chemical Oxygen Demand and concentration of RV5 in water irradiated by 366 nm wavelength light has been investigated. Photo degradation efficiency in organic matter removal approaches direct vacuum photolysis of 185 nm or 190 nm. Reaction follows zero-order kinetics with a constant speed of 1,5999 mg d’O2.l^-1.min^-1. While RV5 decolourization corresponds to a first order reaction with a constant speed of 0,0104 min^-1. This natural treatment is allowed to remove 55 % of COD and 44,3 % of the coloring.