Removal of Basic Dye Bromophenol Blue from aqueous solution by Electrocoagulation using Al – Fe Electrodes: Kinetics, Equilibrium and Thermodynamics Studies.

Abstract

Electrocoagulation (EC) in a batch cell with Al anode and Fe cathode in monopolar parallel (MP) connection was used for the removal of basic dye, Bromophenol Blue (BPB). The effects of current density, pH, temperature and initial dye concentration, on the process were investigated. Equlibrium data were analyzed using four model equations: Langmuir, Freudlinch, Temkin and Dubinin–Radushkevich. Data obtained from the time dependent electrocoagulation removal of BPB were analyzed with pseudo-first-order, pseudo-second-order and Elovic kinetic models. The study showed that the process depend on current density, temperature, pH and initial dye concentration. The process attained equilibrium after 15 minutes at 30 oC, all the isotherm models fitted the data with R2 > 0.9. The maximum removal capacity Qm value of 166.50 mg g-1 was obtained for the study while the first order kinetic model best described the process based on the lower values of %SSE. The calculated thermodynamics parameters (∆Go, ∆Ho and ∆So) indicated that the process is spontaneous and endothermic in nature.