Abstract:In order to investigate the environmental activity of lead/arsenic in copper smelting slag, its distribution pattern, and the relationship between the lead and arsenic content and the slag components, as well as lay a foundation for the control of lead and arsenic in smelting process and for the prevention of lead and arsenic pollution in copper smelting slag/tailings, various analytical techniques, including ICP-OES, XRF, XRD, chemical analysis, chemical phase analysis, SEM, and MLA, were employed to analyze the leaching characteristics of lead and arsenic in typical copper smelting slag samples from four different sources. The results indicate that the smelting slag is primarily composed of iron and silica, consisting of fayalite and magnetite, with lead accounting for 0.2% to 2% and arsenic accounting for 0.02% to 0.6%. Lead and arsenic primarily exist in residual forms, with over 70% of lead present as other lead chemical phases and more than 90% of arsenic existing in the form of arsenates and glassy arsenic phases. The leaching concentration of lead and arsenic increases as the particle size of the smelting slag decreases and the crystallinity deteriorates. In some samples with particle size of -0.074 mm, the leachable concentrations of lead and arsenic exceed the U.S. EPA standard limit (5 mg/L). Additionally, lead and arsenic are mainly endowed in silicate glassy mineral phases. A significant positive correlation exists between the lead and alkalinity, the arsenic and alkalinity, as well as the contents of lead and arsenic in the glassy phase.