The alternating and direct current effect on the elimination of cationic and anionic dye from aqueous solutions by electrocoagulation and coagulation flocculation

Abstract

In this study, we investigated the effect of alternating current (AC) and direct current (DC) on the elimination of methylene blue (MB) and indigo carmine (IC) by the electrocoagulation process using two Pb electrodes in comparison with the coagulation-flocculation process. Different parameters influencing the elimination of these dyes were studied, namely initial dye concentration, initial pH, voltage, temperature, coagulant and flocculant concentration and current density. The elimination of MB reached 98.8% with AC and 97.3% with DC at current density of 0.5 A/m 3 and pH of 7.0. However, the energy consumed was lower in the case of AC (4.89 9 10 -6 kWh/m 3 ) than DC (7.6 9 10 -6 kWh/m 3 ). The elimination was also faster in the case of AC (0.47 mg L -1 /min) than the DC (0.066 mg L -1 /min). The same behavior was observed with the IC where the effectiveness of dye elimination was, respectively, 98.5 and 100% with an energy consumed (E c ) of 4.35 9 10 -5 and 2.03 9 10 -6 kWh/m 3 , respectively, with DC and AC. The adsorption kinetic data were obtained using pseudo-firstorder and pseudo-second-order models. The pseudo-second-order was more appropriate describing the adsorption kinetics of methylene blue and the pseudo-first-order was more appropriate describing the adsorption kinetics of indigo carmine. Langmuir, Freundlich and Sips models were used to optimize the elimination dye process. The Sips model displayed the best fit of the equilibrium data.

Removal of Aniline Blue from Textile Wastewater using Electrocoagulation with the Application of the Response Surface Approach

“…Freundlich, Langmuir, Tempkin, Dubinin, and Sips isotherm models were used to investigate the adsorption model of experimental data and maximum uptake of pollutants from the aqueous phase to the solid phase [4,9,10]. Then, the most appropriate correlation for the equilibrium curves was determined.…”

“…This dye-containing wastewater is harmful to human and aquatic life because most kinds of these dyes might cause toxicity, cancer, or mutations to living organisms [3]. Therefore, there is a growing requirement for intensive treatment of wastewater in order to protect the environment from these harmful chemicals and dyes, because of their stability, low bio degradability, and high toxicity [4].…”

Adsorption of Basic Violet 16 dye from aqueous solution onto mucilaginous seeds of Salvia sclarea: kinetics and isotherms studies

“…It is widely used in textile, leather industries and is also a well-known water tracer fluorescent [7]. Various methods such as chemical oxidation [9,10], ozonation [11], aerobic and anaerobic microbial degradation [12], coagulationflocculation [13] and membrane process [14] were used for removal of dyes. The mentioned processes have many disadvantages such as high reagents and energy requirements and generation of toxic sludge which again needs safe disposal [15].…”

Photovoltaic Energy-Assisted Electrocoagulation of a Synthetic Textile Effluent

“…The electrocoagulation process is deemed an economical and environmental choice to minimize the drawbacks of conventional wastewater treatment technologies [13]; it provides a number of benefits, such as low cost, compatibility, and safety [14]. In addition, electrocoagulation has been proven to eliminate complex contaminants in wastewater that require a combination of physicochemical and biological methods [15][16][17].…”