Chromium Removal from Aqueous System and Industrial Wastewater by Agricultural Wastes

ABSTRACT

This study involved the development of formaldehyde-treated, deseeded sunflower head waste–based biosorbent (FSH) for the biosorption of Cr(VI) from aqueous solution and industrial wastewater. Batch-mode experiments were conducted to determine the kinetics, sorption isotherms, effect of pH, initial Cr(VI) concentration, biosorbent dose, and contact time. The results demonstrated that FSH can sequester Cr(VI) from the aqueous solution. The maximum sorption occurred at pH = 2.0, biosorbent dose = 4.0 g/L, concentration of 100 mg/L at 25°C at 180 rpm after 2 h contact time. The FSH had an adsorption capacity of 7.85 mg/g for Cr(VI) removal at pH 2.0. The rate of adsorption was rapid, and equilibrium was attained within 2 h. The equilibrium sorption data fitted the Langmuir isotherm model, which was further confirmed by the chi-square test.

KEYWORDS:

• biosorption
• formaldehyde
• industrial wastewater
• Langmuir
• SEM
• sunflower

ACKNOWLEDGMENTS

The present work was supported by Council of Scientific and Industrial Research (CSIR), Government of India, New Delhi, in the form of Senior Research Fellowship. The authors express their thanks for financial support to this work.