REMOVAL OF Pb2+ AND Cr3+ USING RICE HUSK AS BIOSORBENT

: The biosorption process and agricultural waste to treat heavy metals has drawn much attention. This method seems to be a more economical, envchromiummentally friendly, and simple way for removing heavy metals from effluents. The study was conducted to explore the efficiency of the biosorption process utilizing rice husk to remove Pb 2+ and Cr 3+ from synthetic wastewater. Biosorption studies at different operating parameters, such as biosorbent dosage (0.5-5.0 g), pH (pH2– 8), contact time (15-120 minutes), and initial heavy metal concentration (10-100 mg/L), were conducted in batch experiments. The highest performance for Pb 2+ and Cr 3+ biosorption was found at 5.0g biosorbent dosage of spent mushroom compost, unadjusted pH 6, 10 minutes of contact time, and 10 mg/L of initial concentration. The study was well fitted to the Langmuir isotherm model (R 2 > 0.90) for Pb 2+ and Cr 3+ biosorption, which are much greater compared to the Freundlich model. Solvent of 0.1N Sulphuric acid showed higher desorption of Pb 2+ (89%) and Cr 3+ (86%) adsorption-desorption process can be continued till seven cycles efficiently. In conclusion, the rice husk has the potential to be an effective biosorbent for removing Pb 2+ and Cr 3+ from synthetic wastewater.