Adsorptive removal of Cu(II) from aqueous solutions using a novel macroporous bead adsorbent based on poly(vinyl alcohol)/sodium alginate/KMnO4 modified biochar

In this study, a novel adsorbent was synthesized through the entrapment of KMnO4 modified biochar (MB) in poly(vinyl alcohol)/sodium alginate hydrogel bead (PSMB) and then tested to determine its capacity for removal of Cu(II) from aqueous solutions. The maximum Cu(II) adsorption capacity estimated with Langmuir isotherm modeling was 87.07 mg/g of PSMB, which was higher than that of previously reported adsorbents. PSMB had a good selectivity towards Cu(II) as well as high anti-interference ability. The main species for Cu(II) adsorption likely were the inner-sphere Cu-O complexes, as indicated by the results of spectral analyses. The PSMB was easily collected and exhibited a minimal loss of adsorption capacity after 10 adsorption/regeneration cycles. The effective removal of Cu(II) from environmental water samples with relative low treatment cost indicated a possibility for practical application. (C) 2019 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.