Mussel-inspired magnetic adsorbent: Adsorption/reduction treatment for the toxic Cr(VI) from simulated wastewater

A novel magnetic adsorbent, poly(catechol-1,4-butanediamine)-coated Fe3O4 composite (Fe3O4@PCBA), was successfully fabricated via an easy and gentle method according to the mussel-inspired adhesion property of polydopamine. Effects of many factors on the adsorption performance of Fe3O4@PCBA for Cr(VI) were investigated, including temperature, pH value, contacting time, adsorbent dosage, and initial Cr(VI) concentration. The thermodynamics, adsorption isotherm, kinetics, and intraparticle diffusion of adsorption were also studied systematically. Results indicated that the removal rate of Cr(VI) was approximately close to 100% when the initial concentration was less than 120 mg/L, and the maximum uptake capacity of Fe3O4@PCBA for Cr(VI) was 280.11 mg/g complied with Langmuir isotherm model. Accordingly, the nocuous Cr(VI) could be partially reduced to Cr(III) during the adsorption period. Hopefully, this strategy could be extended to prepare series of magnetic Fe3O4@catechol-amine adsorbents with different amino and phenolic hydroxyl groups for Cr(VI) removal. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46530.