Treatment of coffee processing wastewater using Moringa stenopetala seed powder: Removal of turbidity and chemical oxygen demand

Abstract

In Ethiopia, the wastewater generated from coffee processing industries is often directly discharged to the river due to lack of monitoring facilities. This resulting in water contamination causing risks to entire ecological system and human well-being of the society needs an urgent attention by the environment specialists. Hence, the current research is aimed to investigate the potential of Moringa stenopetala seed powder for the improvement of physicochemical and bacteriological load of coffee processing wastewater. The optimization of adsorbent dose and contact time on the reduction of turbidity and COD were done by the standard method. The Moringa stenopetala seeds were collected from Dilla University campus and ground to fine powder. The obtained powder was characterized by scanning electron microscope and X-ray diffractometer and wastewater was collected from coffee processing site. The SEM and XRD results revealed that Moringa stenopetala seed powder having an amorphous morphology for retention of impurity load. After treatment with this seed powder, the physicochemical and biological quality of the wastewater was significantly improved and there is a 99.43% and 99.16% reduction of turbidity and COD were reached respectively at adsorbent dose of 80 mg L−1 and contact time of 60 min and 45 min respectively. This current research proved that Moringa stenopetala seed powder has a promising potential to improve physicochemical and biological quality of wastewater. Adopting this system can be economically, environmentally, and socially feasible to address wastewater problems. Further research on surface modification of this adsorbent is needed to enhance its removal efficiency.