Abstract
This study was conducted to analyse the biosorption of manganese(II) from aqueous solutions by rice husk ash (RHA) in a continuous packed column reactor. Different column parameters were used, such as influent Mn(II) concentration, bed height and flow rate. The results showed that the equilibrium adsorption (mg g−1) has increased after increasing the influent Mn(II) concentration but decreased when increasing the flow rate and the bed height. When the influent Mn(II) concentration was expanded from 5 to 20 mg l−1 at a fixed bed height and flow rate, then Mn(II) uptake also expanded from 2.73 to 4.76 mg g−1. Similarly, by increasing the bed height from 7.5 to 22.5 cm and flow rate from 5 to 15 ml min−1, the adsorption capacity of Mn(II) decreased from 7.57 to 2.97 mg g−1 and 3.61 to 1.90 mg g−1, respectively. In addition, several empirical models such as Adams–Bohart, Wolborska, Thomas and Yoon–Nelson models were used in this study to investigate the breakthrough curves in a simple way. The best fitting was obtained with Adams–Bohart and Wolborska models which showed high degree of fitting (r2 ≥ 0.82). So Bohart–Adams and Wolborska models were the most suitable to estimate breakthrough curves obtained under varying experimental conditions.
Acknowledgement
This study was supported by the National Scientific and Technological Supporting Project, China (2013BAJ12B01).