Modeling Date Palm Trunk Fibers (DPTF) Packed Bed Adsorption Performances for Cadmium Removal from Aqueous Wastewater

Abstract

In this study, the potential of a low-cost bio-adsorbent, taken directly from Date Palm Trunk Fibers (DPTF) agricultural wastes, for cadmium ions removal from wastewaters is examined. The performances of this adsorbent are evaluated by building breakthrough curves at different bed heights and flow rates while keeping other parameters, such as the initial feed concentration, pH, and particle size, constant. The results indicate that the maximum cadmium adsorption capacity of DTPF can be obtained from the Thomas model as 51.5 mg/g with the most extended mass transfer zone of 83 min at the lowest flow rate at 5 ml/min. The saturation concentrations (NO) and the rate constant (kab) obtained from the BDST (bed depth service time) model are 7022.16 mg/l and 0.0536 l/mg.min, respectively. Using the Yon-Nelsen Model, it is found that operating at a lower flow rate leads to a larger value of the elapsed needed time to reach a 50% breakthrough. The Wolborska model indicates that the bed capacity increases with decreasing the flow rate, and the adsorbent can achieve a greater external mass transfer kinetic coefficient (2.271/min) at a higher flow rate.