In-situ Pb2+ remediation using nano iron particles

Originally, application of nano zero valent iron (nzvi) particles for the removal of lead (pb2+) in porous media was studied.at first, stabilized nzvi (s-nzvi) was prepared and characterized, then used in batch and continuous systems. based on thebatch experiments, corresponding reaction kinetics well fitted with the pseudo-first-order adsorption model, and reactionrate ranged from 0.01 to 0.04 g/mg/min depend on solution ph and the molar ratio between fe and pb. in batch tests,optimal condition with more than 90% removal efficiency at 60 min was observed at a ph range of 4 to 6 and fe/pb ratiomore than 2.5. continuous experiments exposed that pb2+ remediation was as well influenced by seepage velocity, grainsize, and type of porous media. the maximum pb2+ removal efficiency in batch and bench-scale systems were 97% and81%, correspondingly. the results have shown the ability of s-nzvi to use in permeable reactive barriers, as an efficientadsorbent for pb2+, because of its excellent stability, high reducing power, and a large surface area.