ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Multivariate response optimization of Pb(II) extraction from wastewater using Box-Behnken design

Vijayalakshmi Rajadurai, Brinda Lakshmi Anguraj, Muthuvel Inbasekaran, and Hemalatha Manivannan

Department of Chemical Engineering, Saveetha Engineering College, Chennai, India

E-mail: brindagrace@gmail.com

Received: 3 July 2021  Accepted: 28 December 2021

Abstract:

This study describes the determination of Pb(II) in wastewater by the application of solvent extraction using the halogen-free ionic liquid, 1-butyl-3-methylimidazolium octyl sulfate [BMIM][OCTSO₄]. The RSM based on Box-Behnken Design (BBD) was used to optimize the experimental parameters such as extraction time, pH, feed concentration, and the amount of ionic liquid respectively, and their interaction effects that affect the extraction performance of lead. The predicted optimum working conditions are as follows: feed concentration—10 ppm, pH—4.5, shaking time—105 min, and amount of IL—3 g. Under this optimum value, the removal efficiency of lead was obtained at more than 99%. Furthermore, the statistical results revealed that the quadratic model was best fitted to the experimental data at 95% confidence level, which was analyzed by Analysis of Variance. Besides, factors like feed concentration and amount of ionic liquid and their interactions have a positive effect on Pb(II) extraction rate. Based on the analysis, the industrial effluents were treated to determine the physicochemical characteristics of lead before and after extraction. The concentration of Pb²⁺ in industrial effluents was reduced effectively using the ionic liquid and determined by Atomic Absorption Spectroscopy.

Graphical abstract

Keywords: ANOVA; Box-Behnken design; Industrial effluents; Ionic liquid; Lead; Solvent extraction

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-021-02054-3

Chemical Papers 76 (5) 2677–2690 (2022)