Biosorption of Bisphenol A by Agricultural Waste: A Kinetic and Isothermic Study

Bisphenol A is a phenolic compound, which even in low concentration, is harmful and toxic for human and environment and is abundantly found in industrial effluents. In the present study, the removal of bisphenol A by Canola wastes, was investigated.
In this experimental study, first canola waste was collected and their stem was removed, and then were dried in fur (105°C for 24h) and were sized using ASTM. The changes of pH, adsorbent dosage, contact time, and bisphenol A concentration, were assessed and the remaining concentration of bisphenol A was analyzed using HPLC. Equilibrium data were investigated by various types of adsorption isotherms and kinetics.
In this study, the specific surface area of adsorbent was 52.5m2/g. The maximum absorption of bisphenol A was obtained at pH=3, adsorbent dosage was 4g/L and contact time was 75 min. The bisphenol A removal efficiency decreased from 98.9% to 65.4% with increasing concentrations of bisphenol A from 25 to 200mg/L. Also, the results of adsorption study showed the highest correlation with the Langmuir isotherm and pseudo second-order kinetic model.
According to the results of the current study, bisphenol adsorbent can be used as an effective and low-cost adsorbent to treat the industrial wastewater and/or aqueous solution containing phenolic compounds.