Removal of trace boron from aqueous solution using iminobis-(propylene glycol) modified chitosan beads

In this paper, a new boron chelating chitosan based polymer with multi-hydroxyl iminobis (propylene glycol) (IBPG) functions was prepared. A cross-linked chitosan (CCTS) with 2.70 mmol g−1 amine content was modified with excess amount of glycidol at pH 7 and boron chelating resin with IBPG functions (4.60 mmol g−1) was obtained. The boron chelating ability of the resulting resin was investigated under different experimental conditions (pH, foreign ions). This prepared material was evaluated by FT-IR spectra and UV spectra analysis. The IBPG modified CCTS resin was demonstrated to have a boron loading capacity of 2.2 ± 0.05 mmol g−1 within 45 min. Desorption and resin regeneration studies were carried out to determine the effectiveness of the synthesized resin with HCl and NaOH respectively. The adsorption test indicated that the chitosan based chelating resin with IBPG functions exhibited higher selectivity of boron (2.05 mmol g−1) in the presence of foreign ions especially Fe(III).