A novel antibacterial biocomposite based on magnetic peanut husk for the removal of trimethoprim in solution: Adsorption and mechanism study

A novel adsorbent (MPN-Bet) with antibacterial and magnetic properties was synthesized via the functionalization of peanut husk (a low-cost material) with Fe3O4 and betaine. Results from the characterization studies confirmed that the enhanced efficiency of peanut husk as an adsorbent was due to the alteration in its surface nature and physicochemical properties by these modification agents. MPN-Bet possessed good efficiency for the sequestration of trimethoprim (TMP) from solution. The experimental adsorption capacity of 20.3 ± 0.9 mg g−1 was recorded with the process being exothermic in nature. The physisorption and chemisorption processes were found play active roles in the adsorption process albeit the latter being the dominant. Regeneration studies showed MPN-Bet loaded TMP was highly reusable after treatment with 0.1 mol L−1 NaCl. The assessment of the antibacterial properties of MPN-Bet indicated that MPN-Bet could effectively limit the growth of E. coli and S. aureus without causing damage to other living organisms (i.e. biocompatible). These excellent properties of MPN-Bet coupled with its good reusability, high stability and easy separation from mixtures promote its prospects for practical wastewater remediation.