utilization of zerovalent iron (zvi) particles produced fromsteel industry waste for in-situ remediation ofgroundwatercontaminated withorgano- chlorine pesticideheptachlor

treatment of ground water contaminated with halogenated pesticides is a challenging task. thispaper focuses on preparation, characterization and treatment of heptachlor by iron particles synthesized fromsteel industry waste (s-zvi). the bof sludge, which is dumped in landfills, is an iron rich source and wasused as the source material for s-zvi synthesis. the vital step was reducing agent sodium borohydrideoptimization and a high dose of 3.5g/10ml of dose was required for production of s-zvi. the average particlesize for s-zvi and after modifying using surfactant paa (5%) was 1660 nm and 300 nm, respectively.crystalline structure of s-zvi and a diverse chemical composition was found with high contents of na, ca andmg. reduction of heptachlor was studied in batch reactors using s-zvi, paa modified s-zvi, tween 20modified s-zvi and pure zvi. after 48h, the reduction efficiency of heptachlor, by various forms of zvi, wasfound to be 87%, 89%, 75 % and 93% respectively. the observed dechlorination rate constant of heptachlorby paa modified s-zvi was found to be the highest (1.959/hr) followed by tween 20 modified s-zvi (1.106/hr), unmodified s-zvi (0.526 /hr) and pure zvi (0.09 /hr). the surface area normalised rate constant (ksa)were found to be 0.2884 l/hr/m2, 0.1074 l/hr/m2, 0.06606 l/hr/m2 , and 0.000486 l/hr/m2 for s-zvi, paamodified s-zvi, tween 20 modified s-zvi, and pure zvi respectively.