Decolourization of Reactive Blue 19 Dye Effluents by Electrocoagulation in a Batch Recycle New Electrochemical Reactor

The efficiency of electrocoagulation to treat reactive blue 19 dye effluent was investigated, using a recycle batch reactor with aluminium electrodes. A new cell arrangement was suggested where the anode consisted of an array of horizontal aluminium cylinders embedded between an upper and a lower aluminium screen cathode. An advantage offered by the horizontal tubes used as anode is the possibility of using the inner side of these tubes as a heat exchanger to control the reaction temperature if needed. Different operating parameters, affecting the efficiency of color and COD removal, such as current density, flow rate, initial dye concentration, electrolyte concentration and pH were studied. Increasing the current density and the electrolyte concentration increased the color and COD removal. Inversely, a higher flow rate and a higher initial dye concentration decreased the removal rate. The pH of the waste needed to be neutral or nearly neutral to accomplish a high efficiency. A color removal of 97.4% and COD removal of 93% were achieved under optimum operating conditions. Electrical energy consmption ranged from 1.08 to 33.4 kWh/kg dye removed depending on the operating conditions.