The effect of ground copper slag on the hydration kinetics and mechanical properties of portland pozzolana cement

This study reports the effect of fine ground copper slag on hydration kinetics and mechanical properties of Portland Pozzolana cement (PPC). PPC replacement level 0, 5 & 10% by mass of ground copper slag of particle size 4.6 μm & 8.8 μm (d₅₀) were tested and evaluated for mechanical properties such as compressive strength, hydration kinetics and leachability of heavy metals. Mortar compressive strength worked out in compliance with IS-4031. The hydration kinetics was studied using powder XRD and Isothermal conduction calorimeter. Leachability of each specimen was evaluated following USEPA guidelines. The presence of ground copper slag in cementitious system manipulates its setting behavior. Increased PPC replacement levels by 10% increases strength by over 5% from 28 day onwards. The result of hydration study reveals participation of ground copper slag in hydration of PPC cement. Hydration kinetics of the PPC cement pastes studied with copper slag exhibits similar trend. However quantum of energy released differs with varying % of ground copper slag. The leaching results indicated that selected heavy metal ions from the cement matrix was low and did not exceed the US-EPA limits. The study indicates potential beneficial aspects of ground copper slag as a substitute material in PPC for conserving natural resources, energy and reduces pollution.