Kinetics, isothermal and thermodynamics studies of electrocoagulation removal of basic dye rhodamine B from aqueous solution using steel electrodes

Abideen Idowu Adeogun,Ramesh Babu Balakrishnan

doi:10.1007/s13201-015-0337-4

Abstract

Electrocoagulation was used for the removal of basic dye rhodamine B from aqueous solution, and the process was carried out in a batch electrochemical cell with steel electrodes in monopolar connection. The effects of some important parameters such as current density, pH, temperature and initial dye concentration, on the process, were investigated. Equilibrium was attained after 10 min at 30 °C. Pseudo-first-order, pseudo-second-order, Elovich and Avrami kinetic models were used to test the experimental data in order to elucidate the kinetic adsorption process; pseudo-first-order and Avrami models best fitted the data. Experimental data were analysed using six model equations: Langmuir, Freudlinch, Redlich–Peterson, Temkin, Dubinin–Radushkevich and Sips isotherms and it was found that the data fitted well with Sips isotherm model. The study showed that the process depends on current density, temperature, pH and initial dye concentration. The calculated thermodynamics parameters (Delta G^circ ,;Delta H^circ ;{text{and}};Delta S{^circ }) indicated that the process is spontaneous and endothermic in nature.

Highlights

Advanced technologies for industrialization and urbanization have substantially contributed to environmental degradation, with the aquatic environment greatly affected, through the discharge of industrial wastewaters and domestic wastes (Senthilkumar et al 2000; Amini et al 2008)
Electrocoagulation was used for the removal of basic dye rhodamine B from aqueous solution, and the process was carried out in a batch electrochemical cell with steel electrodes in monopolar connection
This study presents the results of the laboratory scale studies on the electrocoagulation removal of rhodamine B from aqueous solution

Summary

Introduction

Advanced technologies for industrialization and urbanization have substantially contributed to environmental degradation, with the aquatic environment greatly affected, through the discharge of industrial wastewaters and domestic wastes (Senthilkumar et al 2000; Amini et al 2008). The residual dyes from different sources such as textile, paper and pulp, dye and dye intermediates, pharmaceutical, tannery and kraft bleaching industries are considered as organic coloured pollutants (Rajgopalan 1995; Routh 1998; Kolpin et al 2000; Ali and Sreekrishnan 2001) These industries utilize large quantities of a number of dyes whose residues lead to large amount of coloured wastewaters, toxic and even carcinogenic, posing serious hazard to aquatic living organisms. Rhodamine B, a basic dye with molecular formula C28H31N2O3Cl, IUPAC Name: N-[9-(ortho-carboxyphenyl)-6(diethylamino)-3H-xanthen-3-yli-dene]diethylammonium chloride) and the chemical structure indicated, is a highly water soluble red dye of the xanthene class It is widely used in textiles and food stuffs and is a wellknown water tracer fluorescent (Richardson et al 2004).

Methods

Discussion

Conclusion