Fixed bed column study for pesticide removal using silver nanoparticles-embedded polyurethane foam and glass beads

Abstract

This study reports the effectiveness of silver nanoparticles coated onto polyurethane foam (CPU), fused into polyurethane foam (FPU), and glass beads in a fixed bed column for removal of pesticide “Chlorpyrifos.” Silver nanoparticles coated on substrates were synthesized in laboratory using hibiscus leaf extract (SNP) and was compared with commercial silver nanoparticles (CNP). Characterization of silver nanoparticles and its interaction with the substrate were probed using XRD, TEM, and FTIR, respectively. Experiments were conducted by varying flow rate (20–40 mL/h) with a fixed bed height and pesticide concentration. The maximum removal of pesticide was obtained as 92% and 94% for CPU; 90% and 96% for FPU; 81% and 72% for glass beads with SNP and CNP, respectively, at 20 mL/h flow rate. A decrease in removal efficiency and breakpoint time was observed with an increase in flow rate of pesticide-laden water. The outcome of the study reveals that the polyurethane foam as substrate for silver nanoparticles is more effective for the removal of pesticide from the aqueous solution, which can be further developed into continuous portable modules at commercial scale.