REMOVAL OF ACID RED 1 DYE POLLUTANT FROM CONTAMINATED WATERS BY ELECTROCOAGULATION METHOD USING A RECIRCULATING TUBULAR REACTOR

Abstract

Different types of the dye are considered as the major environmental pollutants, and even their very low concentration can affect the transparency and aesthetic quality of the surface waters. Acid Red 1 (AR1) is one of the synthetic azo dyes extensively used in textile industries. The present study aims to examine the efficiency of electrocoagulation method on the removal of AR1 from contaminated waters in a recirculating tubular reactor using iron electrodes. Numerous parameters such as current density, pH, electrolyte concentration, flow rate, and the concentration of dye pollutants were studied. The obtained spectrophotometric results indicated that with an increase in current density and electrolyte concentration, the percentage of dye removal increases, but with an increase in dye concentration, pH, and the flow rate of solution into the reactor, the rate of pollutant removal decreases. For 2 litters of the solution containing 30 mg/L AR1 with a current density of 0.011 A/cm2, pH of 6.8, electrolysis time of 20 minutes, flow rate of 45.45 ml/s, and electrolyte concentration of 0.08 g/L, dye removal percentage of about 95% was obtained by electrocoagulation in a recirculating tubular reactor.