Efficient removal of toxic phosphate anions from aqueous environment using pectin based quaternary amino anion exchanger

Pectin based quaternary amino anion exchanger (Pc-QAE) was prepared using simple crosslinking polymerization method. This anion exchanger was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Pc-QAE was applied for the removal of phosphate anion from the aqueous solution. The adsorption process which was pH dependent showed maximum adsorption of phosphate anions at pH 7. Pc-QAE showed good monolayer adsorption capacity for phosphate anions which demonstrated its good capability towards Langmuir isotherm model. Moreover, the adsorption was evaluated thermodynamically and the negative value of Gibbs free energy (−1.791 KJ/mol) revealed the spontaneity of adsorption process. The value of ΔH° and ΔS° were found to be 15.28 and 49.48 KJ/mol, respectively representing the endothermic nature and enhancement in degree of freedom due to the adsorption process.