Modeling and analysis of dynamic malachite green adsorption onto natural clay

Abstract

A continuous fixed bed (column) study was carried out by using natural clay of  Safi  as an adsorbent for the removal of malachite green  dye, from aqueous solutions. The effects of the operation conditions of the fixed bed on the breakthrough curve were investigated using continuous-flow column operation by varying the bed height (0.15–0.3 m) and the feed concentrations (160 – 260 mg/l). Breakthrough analysis revealed that early saturation and lower MG removal takes place at higher flow rate and at higher concentrations.

 Adams- Bohart  was applied to experimental data to determine the characteristic parameters of the column that are useful for process design. the Adams- Bohart model was only used to predict the initial part of the dynamic process. An attempt has also been made to model the data generated from column studies using the empirical relationship based on Bohart–Adams model, the bed depth service time analysis (BDST) model was applied at different concentrations to predict the breakthrough curves. The model is found suitable for describing the adsorption process of the dynamic behaviour of the MG column and the data were in good agreement with BDST model