Degradation of aqueous carbon tetrachloride by nanoscale zerovalent copper on a cation resin

Nanoscale zerovalent copper supported on a cation resin was successfully synthesized to enhance the removal of carbon tetrachloride (CCl4) from contaminated water. The use of the cation resin as a support prevents the reduction of surface area due to agglomeration of nanoscale zerovalent copper particles. Moreover, the cation resin recycles the copper ions resulting from the reaction between CCl4 and Cu0 by simultaneous ion exchange. The decline in the amount of CCl4 in aqueous solution results from the combined effects of degradation by nanoscale zerovalent copper and sorption by the cation resin; thus the amount of CCl4 both in aqueous solution and sorbed onto the resin were measured. The pseudo-first-order rate constant normalized by the surface-area and the mass concentration of nanoscale zerovalent copper (kSA) was 2.1 ± 0.1 × 10−2 l h−1 m−2, approximately twenty times that of commercial powdered zerovalent copper (0.04 mm). Due to the exchange between Cu2+ and the strongly acidic ions (H+ or Na+), the pH was between 3 and 4 in unbuffered solution and Cu2+ at the concentration of less than 0.1 mg l−1 was measured after the dechlorination reaction. In the above-ground application, resin as a support would facilitate the development of a process that could be designed for convenient emplacement and regeneration of porous reductive medium.