A durable luminescent ionic polymer for rapid detection and efficient removal of toxic Cr2O72−

Abstract

A durable luminescent imidazolium-based main-chain ionic polymer (IMIP-Br) was prepared by a facile quaternization reaction of tri(4-imidazolylphenyl)amine and 1,2,4,5-tetrakis(bromomethyl)benzene. IMIP-Br can not only detect Cr₂O₇²⁻ rapidly and estimate its concentration in water, but also capture Cr₂O₇²⁻ quickly via anion exchange. The tremendous exchange capacity of 318 mg g⁻¹ and remarkable efficiency of 92.6% are achieved using an equivalent amount of IMIP-Br. The separation and recycling procedures are simplified by the integration of Fe₃O₄ particles and IMIP-Br. The resultant IMIP-Fe shows outstanding enrichment ability, good regenerative ability and superior recyclability for removal of Cr₂O₇²⁻. The combination of promising removal performances and simple magnetic separation endows IMIP-Fe with great promises for capture and separation of Cr₂O₇²⁻ from contaminated water systems.