Adsorptive remediation of Pb(II) from aqueous media using Schleichera oleosa bark

Abstract

Abstract Adsorption characteristics of Schleichera oleosa bark for sequestering Pb(II) from aqueous solution were explored. Various physicochemical parameters such as the influence of initial metal concentration, contact time, pH, dose, and temperature were investigated for achieving conditions for maximum Pb(II) removal via batch mode. The adsorbent was characterized for its functional groups, physical morphology, and elemental composition by Fourier transform infrared spectrometer (FTIR), and Scanning Electron Microscopy (SEM) equipped with Energy dispersive X-ray (EDX). Statistical analysis and optimization of the process were done by response surface methodology (RSM) using Box–Behnken design with dose, initial concentration, and the temperature is taken as independent variables. Analysis of variance (ANOVA) indicated the successful fitness of experimental data into the quadratic model. Isotherm and kinetic studies were carried out by fitting experimental data in different adsorption isotherm and kinetic models. Maximum monolayer adsorption capacity based on the Langmuir isotherm model was 69.44 mg g−1. Thermodynamic parameters ( Δ H o and Δ S o ) indicated adsorption process to be spontaneous and endothermic. Breakthrough and exhaustive capacities were 17.5 mg g−1 and 62.5 mg g−1.