Boron removal from aqueous solutions using alginate gel beads in fixed-bed systems

BACKGROUND A column sorption study was carried out using calcium alginate gel beads as adsorbent for the removal of boron from aqueous solutions. The breakthrough curve was obtained as a function of pH, initial concentration of boron, feed flow rate, adsorbent mass and column diameter. The breakthrough capacity values and adsorption percentage of calcium alginate gel for boron were calculated. Column data obtained at different conditions were described using the Adams-Bohart model and bed-depth service time (BDST), derived from the Adams-Bohart equation to predict breakthrough curves and to determine the characteristic column parameters required for process design. RESULTS The maximum adsorption percentage of boron on calcium alginate gel beads using an initial concentration of boron of 50 mg L-1 at pH 11 and room temperature (20±1°C) was calculated to be 55.14%. CONCLUSION The results indicated that calcium alginate can be used in a continuous packed-bed column for boron adsorption. The optimal conditions for boron adsorption were obtained at high pH, higher initial boron concentration, increased column depth and lower flow velocity. © 2014 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.