Removing Bisphenol A from Aqueous Solution by Phosphorylated Cotton in the Presence of Cetyl Trimethyl Ammonium Bromide

Abstract

Removal of bisphenol A (BPA) was investigated by hydrophobic sorption of hemimicelles with phosphorylated cotton (PC) as a sorbent and cetyl trimethyl ammonium bromide (CTAB) as a cationic surfactant. CTAB was sorbed on oppositely charged PC through coulombic attraction and formed hemimicelles at a certain concentration level called critical hemimicellar concentration (CHC). BPA was subsequently sorbed on the sorbent through hydrophobic interaction between the linear hydrocarbon chain of CTAB on hemimicelles and the aromatic alkyl group of BPA. BPA removal was found to be dependent on initial pH and CTAB dosage. Isothermal data of BPA sorption conformed well to the Langmuir model, and the maximum sorption capacity (Q_m) of PC for BPA was 48.78 mg/g. The BPA removal process could be described by a pseudosecond-order kinetic model. The thermodynamic study indicated that the BPA removal process was spontaneous and exothermic.