气候变化领域集成服务门户

This study investigated the adsorption of malathion to copper (Cu) and iron surfaces, including microspheres and pipe specimens similar to those in drinking water infrastructure. The solid phase concentration of malathion on the virgin and used Cu pipe specimens was generally between 0.2 and 1 mg/g. The adsorption capacity for Cu and iron microspheres was greater than those of the pipe specimens because of their higher surface-area-to-volume ratios. Copper materials adsorbed more malathion than comparable iron materials. X-ray photoelectron spectroscopy analysis of Cu and iron surfaces revealed peaks at 164 eV (S 2p) and 135 eV (P 2p), which suggests that malathion chemically bonded to the surfaces of the specimens. Metal oxides likely formed stable bonds with phosphorus through pi conjugation. These findings are the first to show that malathion can chemically adhere to Cu and iron pipe materials. This insight is critical for understanding the decontamination strategies needed for water networks.