Efficiency and chemical recycling capability of magnetite-rich clay towards Eriochrome Black T remediation in the fixed-bed system.

The present study investigates a fixed-bed column by using magnetite-rich clay from Cameroon as an adsorbent for the removal of the Eriochrome Black T (EBT) from aqueous solution. The effect of various parameters such as bed depths and EBT concentrations was investigated. The Adams-Bohart, Thomas and Yoon-Nelson models were applied to adsorption under varying experimental conditions to predict the breakthrough curves and to evaluate the model parameters of the fixed-bed column that can be useful for the process design. The column regeneration studies were carried out for three different sorption-desorption cycles using HCl or NaOH solution at 1 M. The 1 M HCl solution was found to have the best bed regeneration capacity and the fixed-bed could be reused for several sorption-desorption cycles. The elution efficiency of EBT, 75 mg L(-1) was greater than 99.1% for all three cycles.