Abstrait

Optimization of Electrocoagulation (EC) Process for the Purification of Water from 2,4- Dichlorophenoxyacetic Acid (2,4-D) Using Sacrificial Anodes

Nasser M. A. Ghalwa, Ahmed Z. Musabeh, Nader B. Farahat

The present study provides an electrocoagulation process for the adsorption of 2,4 dichlorophenoxyacetic acid (2,4-D) from aqueous solution using sacrificial anodes. The effects of operational parameters such as initial pH, initial concentration, current density, type of electrolyte, salt concentration and temperature on the herbicide and COD removal efficiency have been studied. The optimal operating condition for removal of 2,4-D herbicide were : initial pH of 10, an initial herbicide concentration of 200 mg/L, temperature of 30 oC, current density (62.5, 12.5 and 37.5 mA/cm2) and salt concentration of 1.5g/L by using Fe, S-S and Al respectively. The results showed that the removal percentage for 2,4-D and COD were (88.7% and 71 %), (94.4% and 74.9%) and (93.4 % and 75.3%) by using Fe, S-S and Al electrodes at 60 min respectively. The adsorption equilibriums were analyzed by Langmuir and Freundlich isotherm models. It was found that the data fitted to Langmuir (R2 = 0.9970) better than Freundlich (R2 = 0.9966) model. The removal of 2,4-D exhibited a pseudo second order reaction with rate constant (0.0861, 0.4224 and 0.1903 mol-1dm3 min-1 ) for Fe, S-S and Al electrodes respectively