Preparation and Characterization of Micro Spent Coffee Ground Activated Carbon for the Treatment of Rubber Industry Wastewater

Abstract

This research was conducted to study the preparation and characterization of micro spent coffee ground activated carbon for the treatment of rubber industry wastewater. The rubber industry wastewater contains high concentrations of organic compounds, nitrogen, sulfate and other contaminants. The sulfate can cause the release of the toxic hydrogen sulfide gas that smells like rotten eggs. Early experiments showed that untreated rubber industry wastewater had a turbidity value of 29.8 NTU and a pH value of 8.4. The preparation of micro spent coffee ground activated carbon powder (using high-energy ball milling by carbonization at 400 °C via sodium chloride at 30%) was successful in helping to improve wastewater quality. The micro spent coffee ground activated carbon powder was characterized using scanning electron microscopy. It was found that the porous size of the powder is in the range of 1-4 µm. The analysis of energy dispersive x-ray showed that the micro spent coffee ground activated carbon powder contained mainly C, O, Na and Cl. The result of soaking micro spent coffee ground activated carbon powder in the wastewater for a period of 5 days showed that the treated rubber industry wastewater turbidity value is 9.6 NTU and the pH value is 8.5. It was also found that after being soaked in the wastewater, the micro spent coffee ground activated carbon powder also contained K, Mg, Ca, P and S, on top of C, O, Na and Cl that were originally detected.