Inertization of copper by using blended cement pastes

Abstract

The inertization of copper (II) by using ordinary Portland cement (OPC) or blended Portland cement with granulated blast furnace slag (GBFS) or metakaolin (MK) was studied. Various mixes were prepared by using a water/solid ratio (W/S) of 0.28 (by weight). Two ratios of copper ions (1.0 and 2.0% by weight of the solid binder) were used by adding to the mixing water. The effect of copper chloride on the hydration characteristics of the different cement pastes were investigated by way of the examination of chemically combined water content, compressive strength, as well as X-ray diffraction analysis. Leaching of copper ions from the various hardened cement pastes was examined. The results showed that copper chloride retarded the cement hydration through the formation of double hydroxide of calcium and copper. The obtained leaching results showed a high degree of immobilization of copper ions in the various cement pastes.