Efficient adsorption and desorption of Cu2+ by a novel acid-resistant magnetic weak acid resin

A novel magnetic weak acid resin NDMC-1 was prepared in the presence of methyl acrylate (MA), divinylbenzene (DVB) and titanate coupling agent (TCA) coatedγ-Fe₂O₃ particles. To evaluate the adsorption of Cu²⁺ on the obtained resin NDMC-1, another two magnetic resins NDMC-0 (the precursor of NDMC-1 without hydrolyzation) and NDMO-1 (the synthesized weak acid resin using oleic acid coated γ-Fe₂O₃ ) were chosen for comparison. The results showed that the carboxyl groups were formed after hydrolyzation, and NDMC-1 exhibited a greater adsorption capacity to Cu²⁺. The desorption experiment demonstrated that the desorption ratio at pH 2 (95.14%) was greatly higher than pH 3 (25.97%). Moreover, the magnetic resin NDMC-1 was proved to be stable at pH 2, extending the application of magnetic materials which were always considered to be acid-nonresistant.