Removal characteristics of tanic acid adsorbed on MIEX resin

This study evaluated the removal characteristics of tanic acid (TA) adsorbed on MIEX resin by batch experiments. MIEX resin can effectively remove TA from raw water at pH 6-9. Chloride and sulfate have adverse effect on the removal of TA. Conversely, bicarbonate can further the removal of TA. The Elovich model is the most suitable for depicting the kinetic process, and liquid film diffusion dominates the adsorption rate. The Freundlich model is reliable for describing the adsorption equilibrium. Adsorption is an endothermic, entropy-driving, and thermodynamically spontaneous process. The energy changes confirm the physical adsorption and dominate adsorption behavior. The sodium chloride solution (0.5%) can effectively regenerate the MIEX resin saturated TA, and the regenerated resin can be used circularly. Therefore, MIEX resin is a promising adsorbent for the removal of TA from raw water.