Highly efficient simultaneous biosorption of Hg2+, Pb2+ and Cu2+ by Live yeast Yarrowia lipolytica 70562 following response surface methodology optimization: Kinetic and isotherm study

In this research, biosorption of Hg2+, Pb2+ and Cu2+ from aqueous solution via Yarrowia lipolytica 70562 living mass was described. Correction and dependency of biosorption efficiency to effective variables like pH, initial Hg2+, Pb2+ and Cu2+ concentration, contact time and temperature was studied by central composite design under response surface methodology. Three responses were simultaneously studied by numerical optimization methodology. The optimum biosorption efficiency of Hg2+, Pb2+ and Cu2+ ions at 18, 22 and 25 mg L-1 onto Y. lipolytica 70562 was found to be 99.26%, 101.15% and 99.74% at pH of 6.4 and 25 degrees C after around 8 h under well mixing. Finally, optimum condition for acceptable and repeatable agreement among experimental and real data was explored. The artificial neural network (ANN) model was used for predicting simultaneous biosorption of Hg2+, Pb2+ and Cu2+ ions based on experimental data. It was found that using ANN model with 12 neurons at hidden layer for all three ions, the R-2 of 0.989 and MSE of 993 for Hg2+ ion were obtained. The R-2 of 0.981 and MSE of 1.155 for Pb2+ ion were obtained and also for Cu2+ ion the values of the R-2 and MSE were found to be 0.971 and 1.589, respectively. Langmuir isotherm model was best fitted with the equilibrium experimental. The experimental kinetic data was represented well by using pseudo-second-order model and intraparticle diffusion model. (C) 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.