Electrochemical oxidation for decolorization of Rhodamine-B dye using mixed metal oxide electrode: modeling and optimization

Abstract

In the study the electrochemical oxidation process for decolorization of Rhodamine-B dye was studied using an anode coated with mixed metal oxides: TiO2, RuO2, and IrO2. Batch experimental studies were conducted to assess the effect of four important performance variables, current density, electrolyte concentration, initial pH and electrolysis time, on the decolorization and energy consumption. The process was modeled using an artificial neural network. Response surface methodology using central composite design (CCD) was utilized for optimization of the decolorization process. Based on the experimental design given by CCD, the results obtained by the statistical analysis show that the electrolysis time was the most influential parameter for decolorization whereas the current density had the greatest influence on the energy consumption. According to the optimized results given by the CCD model, maximum color removal of 97% and minimum energy consumption of 1.01 kWh/m3 were predicted in 4.9 minute of electrolysis time, using 0.031 M NaCl concentration at current density 10 mA/cm2 and an initial pH of 3.7. A close conformity was observed between the optimized predicted results and experimental results. The process was found to be efficient and consisted of indirect chemical oxidation producing strong oxidizing agents such as Cl2, HClO and OCl−.

Optimization and efficacy studies of Laccase immobilized on Zein-Polyvinyl pyrrolidone nano fibrous membrane in decolorization of Acid Red 1

“…However, these processes consume excessive amounts of chemicals and also produce large amounts of sludge and do not remove all dyes, thus preventing recycling of treated effluent. The excessive use of chemicals demands increased cost and results in secondary pollution (Kothari & Shah 2020). The physical methods can only transfer the dyestuff from one form to another leaving the pollution problem unsolved.…”

Three-Dimensional Electrochemical Oxidation of Recalcitrant Dye Using Green Iron Microparticles

“…A result of UV-spectrophotometers revealed that only 12% adsorption of Rh-B dye occurs on Fe-MPs in 120 min. During our previous studies, 2D electrochemical oxidation results showed lower removal efficiency while using Na2SO4 as electrolyte [14]. Hence, to improve the efficiency of electrochemical oxidation with Na2SO4, synthesized Fe microparticles were used as a three-dimensional particle electrode/catalyst in this study.…”

“…In our previous study, experiments were performed using the electrolytes NaCl and Na 2 SO 4 during electrochemical oxidation (EO) for decolorization of Rhodamine-B dye. Results showed a lower efficiency of EO with Na 2 SO 4 [14]. A longer time was required with Na 2 SO 4 .…”

“…Application of mixed-metal-oxides-coated titanium plate as anode is effectively practiced for pollutant mineralization in electrolysis [14]. A wide range of metal oxides such as PbO 2, SnO 2, IrO 2, RuO 2 , TiO 2 have been employed as coating material [15,16].…”

An artificial neural network combined with response surface methodology approach for modelling and optimization of the electro-coagulation for cationic dye

“…On the contrary, as the electrocoagulation process is a current induced approach, the removal should be optimized with the energy consumption to achieve cost reduction for industrial application. An artificial neural network (ANN)- response surface methodology (RSM) combination is an emerging reproducible process modelling and optimization technique used by a few researchers [ 21 , 22 ] for dye removal, to save time and cost of experimentation. For future comparable applications, the process must be simulated and optimized.…”