Chromium and nickel exclusion from contaminated water by biomass based carbon microsheet

Abstract

In the present investigation, biomass-based carbon microsheets were synthesized using melamine and corn cob powder as carbon precursors. Three adsorbents were prepared: Carbon microsheets 500 (CMS-500), biomass-based carbon microsheets (BCMS-500), and BCMS-F-500, which were characterized using different analytical techniques. Synthesized adsorbents were optimized for simultaneous adsorption of Ni(II) and Cr(VI) from an aqueous solution. Adsorption was optimized by varying the values of operating parameters, including reaction pH, adsorbent and adsorbate concentration, temperature, and contact time. Maximum adsorption of Cr(VI) was achieved at pH 2 and of Ni(II) was achieved at pH 6 using a 0.5 g/L adsorbent dose and 20 mg/L for each metal concentration. The adsorption of metal ions increased with increasing temperature. The Langmuir adsorption isotherm model best fitted the adsorption of Cr(VI) with both adsorbent and Ni(II) by CMS-500. While the Freundlich adsorption isotherm models were best suited for the adsorption of Ni(II) by BCMS-500, To understand the adsorbent properties, the adsorbent was characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) combined with energy dispersive spectroscopy (EDS), and an X-ray diffractometer (XRD). CMS-500 and BCMS-500 were found to be highly effective adsorbents that can be applied for the effective management of Cr(VI) and Ni(II)-contaminated wastewater.