Assessing biosorbent materials for antibacterial properties and filtration efficiency for potential application in wastewater treatment

Abstract This study investigates the efficacy of certain biosorbents as a filtration method to reduce chlorination and its costs in wastewater treatment. A two-step filtering process was used, with each phase containing 200 mL of bacterially contaminated water that was passed through 100 g of biosorbents. Colony forming units were counted using routine plate counts to determine the bacterial load reduction in filtered and unfiltered water. SEM–EDX analysis was used to investigate changes in particle size, elemental composition and structural changes in biosorbents, whereas hydraulic flow rate estimates determined material permeability. Adsorption decreased bacterial concentrations in all biosorbents. Although cow bone had the highest flow rate (4.62 E-06 m 3 /hr·m 2 ), fly ash and dolomite had the best antibacterial properties, removing 100% of bacteria in the first 200 mL of water passed through biosorbent columns and removing bacteria at the third filtration with a count of less than 150 CFU/mL. Dolomite with activated carbon reduced color, odor, and turbidity. Dolomite and fly ash were found to be less expensive than traditional water filtration systems such as ultrafiltration and reverse osmosis, which are commonly used in industrial wastewater treatment. Future pilot-scale research is needed to fully evaluate these preliminary findings. Importantly, this research proposes a novel approach to wastewater treatment with circular economy benefits, recyclability, and a lower carbon footprint for the biosorbent materials evaluated. This lends support to their potential integration into wastewater treatment systems, which would reduce chlorine dosing and improve sustainability.