Simultaneous adsorption and degradation of γ-HCH by nZVI/Cu bimetallic nanoparticles with activated carbon support.

Cu amended zero valent iron bimetallic nanoparticles were synthesized by doping Cu on the surface of iron. They were incorporated with granular activated carbon (AC) to prepare supported particles (AC-Fe(0)-Cu), which were used to remove γ-HCH. Cu on the surface of iron enhanced the dechlorination activity of Fe(0). The dechlorination rate constant (k(obs)) increased with the Cu loading on the surface of iron and the maximum was achieved with 6.073% Cu. AC as a support was effective for increasing the dispersion of the nanoparticles and avoiding the agglomeration of the metallic nanoparticles. The simultaneous adsorption of γ-HCH on AC accelerated the degradation rate of γ-HCH by the bimetals. After reaction for 165 min, around 99% of γ-HCH was removed by the solids of AC-Fe(0)-Cu. In addition, AC could adsorb the degradation products. The degradation of γ-HCH was mainly through dehydrochlorination and dichloroelmination based on the intermediate products detected by GC/MS.