Adsorption of chromium (Cr) from tannery wastewater using low-cost spent tea leaves adsorbent

Leather tanning is consuming a large quantity of water and discharging a large volume of wastewater. This wastewater contains the high value of COD, BOD, TSS, TDS and heavy metals. In this study, spent tea leaves, a valueless waste produced during the manufacturing of tea beverage, were assessed for their potential to remove chromium (Cr) from tannery wastewater. Cr removal was studied by the batch process with varying adsorbent dose, contact time and pH of the solution to finding optimum conditions. The experiment results showed that maximum removal of Cr by spent tea leaves was 95.42% at 14 g/L of adsorbent dose and pH 10. The maximum adsorption capacity of Cr on tea waste was found 10.64 mg/g.