Adsorptive removal of boron from aqueous solutions with selective resins in high-depth fixed-bed columns

Adsorption method using boron-specific resins is known to be effective for the selective removal from desalinated seawater. This article analyses the performance of high-depth fixed-bed columns for the removal of boron from aqueous solutions. First, the effects of three kinds of resins, flow rates (3, 5, 7, and 10 L/h), bed depths (80, 120, and 160 cm), flow directions (upward and downward), and influent boron concentrations (2.5 and 5 mg/L) on breakthrough curves were investigated. The breakthrough curves obtained in high-depth fixed-bed columns were dependent on the parameters tested. Second, the experimental data were validated by some empirical column adsorption models, such as the Thomas, Yoon–Nelson, Adams–Bohart, and bed-depth service-time models. The breakthrough curves obtained from high-depth column experiments were in good agreement with model predictions. The contact time between adsorbent and adsorbate is an important factor for adsorptive removal. Flow rate and bed depth, affecting the pressure drop, were two critical control parameters for adjusting the contact time. Finally, sensitivity analysis revealed how boron influent concentration, bed mass, flow discharge, rate constant, and adsorption capacity influenced the shape of the breakthrough curve.