A monophosphonic group-functionalized ion-imprinted polymer for a removal of Fe3+ from highly concentrated basic chromium sulfate solution

An ion-imprinted polymer (IIP) with monophosphonic groups was prepared by thermal copolymerization. Bis(2-methacryloxyethyl) phosphate (BMAOP) was used as functional monomer to react with Fe3+ in dimethyl sulfoxide (DMSO). Ethylene glycol dimethacrylate (EGDMA) was used as cross-linker during polymerization process. A suitable molar ratio of BMAOP to Fe3+ was investigated by UV/Vis/NIR Spectrometer and ICP-OES. The obtained results showed that the monophosphonic groups could be selectively combined with Fe3+ in solutions containing other coexisting ions, and the selectivity could be further enhanced by ion-imprinted process. The prepared IIP was used for removing trace Fe3+ from high concentration basic chromium sulfate solutions. After adsorption process, the concentration of Fe3+ could be reduced from 4.486mg L-1 to 0.171mg L-1, which was much lower than the concentration in the solution treated by non-imprinted polymer (NIP). Moreover, the IIP exhibited excellent recyclability after six adsorption-desorption cycles.