Modified agricultural waste biomass with enhanced responsive properties for metal-ion remediation: A green approach

Abstract

Dalbergia sissoo pods, a lignocellulosic nitrogenous waste biomass, was evaluated for sequestering of Cr(VI) from synthetic wastewater. Dalbergia sissoo pods (DSP) were used in three different forms, viz. natural (DSPN), impregnated in the form of hydrated beads (DSPB), and in carbonized form (DSPC) for comparative studies. Batch experiments were performed for the removal of hexavalent chromium. Effects of pH adsorbent dose, initial metal-ion concentration, stirring speed, and contact time were investigated. The removal of metal ions was dependent on the physico-chemical characteristics of the adsorbent, adsorbate concentration, and other studied process parameters. Maximum metal removal for Cr(VI) was observed at pH 2. 0. The experimental data were analyzed based on Freundlich and Langmuir adsorption isotherms. Kinetic studies indicated that the adsorption of metal ions followed a pseudo-second-order equation. © 2012 The Author(s).