Synthesis of Chitosan-Quinoline Biocomposites for Solvent Extraction Applications

A functionalized, significantly hydrophilic Quinoline-Chitosan (QC) biocomposite was chemically synthesized and characterized by ₁H NMR, ₁₃C NMR and FTIR techniques. FTIR spectra revealed a strong interaction between the 2-chloro-3-formyl-7-iminobenzal guinoline scaffold and Chitosan. ₁H NMR results suggested a degree of substitution (DS) ranging from 0.18 to 0.832. The chelating efficiency and selectivity towards transition metal ions, when investigated at pH ranging from 1-8, showed maximum selectivity and affinity for Cu++ as compared to Cd++, Ni++, Co++ at 1-3 pH. This selectivity appeared to be independent of the size and the hardness of the ions. This order in the selectivity was confirmed with potentiometric and spectrophotometric methods and did not depend on the physical form of quinoline-chitosan (QC) biocomposite. Our results prompted us towards further investigating the use of QC as a green depolluting agent.