Adsorption of copper and lead using coffee ground

The contaminated waters have become a serious threat to the environment. The main sources of contaminated water are from industries which releases hazardous heavy metal (Cu, Pb, Zn, Cd, Cr and etc.) In this study, removal of copper and lead has been investigated by using coffee ground as adsorbent. Coffee ground was used as adsorbent to avoid environmental pollution and profitable uses waste. The adsorption of copper and lead was determined by Atomic Adsorption Spectrophotometer (AAS). The effects of relevant parameters including adsorbent dose, initial concentration and contact time adsorption were examined. This experiment was conducted at room temperature and no pH adjustment was made prior to the analysis. Batch adsorption revealed that the amount of copper and lead ion adsorbed increases as the adsorbent dose increase. The decreasing in the percentage removal for coffee ground from 91% to 66 % with initial concentration of 200 mg/L to 250 mg/L respectively. The further increases on the initial concentration is expected to decrease the percentage removal. The equilibrium was achieved at 120 min for copper and lead ions. Based on linear regression, the best fit for copper and lead ions was pseudo second order. The data indicated that the adsorption of copper and lead ions by coffee grounds was best described by Langmuir isotherm model. Result showed both physisorption and chemisorption mechanisms controlled the adsorption rate and capacity respectively.