Adsorption of chromium (VI) by strong alkaline anion exchange fiber in a fixed-bed column: Experiments and models fitting and evaluating

Continuous fixed-bed column studies for Cr (VI) removal from aqueous solutions were carried out by using Strong Alkaline Anion Exchange Fiber (SAAEF) as an absorbent. The effects of initial concentration, pH value, bed depth, temperature and flow rate were examined. The results showed a forward breakthrough point and decreasing exhaustion time with initial concentration, pH value and flow rate increasing. The optimum bed depth could be calculated when the loading density is about 0.20 g cm^-3. The Thomas, Adams-Bohart, Yoon-Nelson and Clark models were applied to predict the adsorption under varying experimental conditions. The Thomas model was in good agreement with the experimental data in representing the whole breakthrough curve while the Adams-Bohart model was valid when c_t/c₀ < 0.5 and the Yoon-Nelson and Clark models were less satisfactory.