Electrocoagulation of azo dye containing synthetic wastewater using monopolar iron electrodes and the characterization of the sludge

Abstract

In this study, the decolourisation of Congo red dye is studied using the natural coagulant Maize Seed Powder (MSP); a suitable alternative for chemical coagulants in electro coagulation (EC) using iron electrodes. The effects of various parameters such as initial dye concentration, pH, applied voltage and time on the decolourisation of dye were studied. The cost of water treatment is increasing due to suspended and colloidal particle load. The coagulation process can be used as a primary step for water and wastewater treatment processes. Among plant materials that have been tested, the seeds of maize have been shown to be one of the most effective primary coagulants in water and wastewater treatment. The removal efficiency of the dye with and without the presence of MSP as a coagulant aid was determined. In the EC process maximum Congo red removal was achieved by using the natural coagulant MSP. Congo red (CR) decolourisation efficiency is 95.23% at a coagulant dosage of 50 mg/lit, pH of 5, operating time of 15 minutes, and a power of 40 volts with iron electrodes. In the absence of coagulant MSP, Congo red decolourisation efficiency was found to be 80.31% at pH of 5, operating time of 15 minutes, and a power of 40 volts with iron electrodes.