Simultaneous removal of chromate and phosphate using different operational combinations for their adsorption on...

Chromate and phosphate are contaminant frequently present in industrial effluents such as tanneries. The objective of this work is to evaluate the efficiency of different operational combinations with dolomite and banana peel for the adsorption of phosphate and chromate in binary solutions. Both adsorbents are residuals from construction and food industries, respectively. Therefore, its use propitiates the reduction of treatment costs and it is an approach to the premises of the circular economy. In this work, the dolomite and banana peel adsorption efficiencies in simple and binary systems were studied. Equilibrium and kinetics tests were carried out in batch and in a fixed bed reactor. Dolomite was found to be selective for the adsorption of phosphate and banana peel for that of chromate. The mixture of adsorbents produced similar phosphate and chromate removal than each adsorbent individually. Therefore, the removals of both contaminants from binary solutions were tested using a fixed bed reactor filled with the mix of adsorbents and the breakthrough curves were analyzed. The obtained removals were 99% of phosphate and 70% of chromate. Finally, a brief discussion was held on the reuse and disposal of saturated adsorbents.