Sequential Design of Experiments for Removal of Methylene Blue Dye by Electrocoagulation Associated with Dissolved-Air System

The present work presents a strategic sequential experimental planning to evaluate the removal of methylene blue dye from aqueous medium by electrocoagulation combined with dissolved air flotation. Effect electrode pairs, spacing, contact time, initial pH, voltage, and pressure were optimized according following response variables: color, final turbidity, removal. best-achieved conditions were: 4 pairs electrodes, 2.5 cm electrolysis time 203 min, pH 4, voltage 32 V, no injection. Among results, it was possible obtain maximum 95.1% dye. analysis surfaces showed that has great influence on characteristic treated effluent. Through study optimization, synthetic effluents have been obtained meet discharge standards current Brazilian environmental legislation.