Adsorptive Removal of Chemical Oxygen Demand from Tannery Wastewater using Industrial By-Products “Blast Furnace Slag”
The characterization of tannery wastewater by analysis of physicochemical parameters showed a high pollution load expressed as a chemical oxygen demand, biological oxygen demand, turbidity, chromium and others. The treatment of these waters is required. The objective of this study is the removal of chemical oxygen demand from this effluent using the adsorption process on the blast furnace slag. The adsorption tests gave a removal rate around 69% with 0.2 g of blast furnaces slag for 25 minutes of contact time. The study of the influence of temperature and pH showed that at room temperature (T = 20 °C) and basic medium, optimal adsorption of pollutant is reached and it follows the Langmuir model. The adsorption kinetics is fast and it is pseudo-second-order type.