Magnetic polar post-cross-linked resin and its adsorption towards salicylic acid from aqueous solution

A novel magnetic polar post-cross-linked resin M-PMD-P-A was prepared, characterized and evaluated for its adsorption towards salicylic acid from aqueous solution. M-PMD-P-A was prepared using suspension polymerization of methyl acrylate (MA) and divinylbenzene (DVB) with addition of oleic acid-coated Fe3O4 nanoparticles, followed by a Friedel-Crafts reaction and an amination reaction. The results indicated that M-PMD-P-A had a large equilibrium capacity towards salicylic acid, and both of the Langmuir and Freundlich models were appropriate for fitting the equilibrium data. The breakthrough capacity at C/C0 = 0.05 and saturated capacity at C/C0 = 0.95 of salicylic acid on M-PMD-P-A were measured to be 45.65 and 62.25 mg/mL wet resin, respectively. A mixture desorption solvent containing 0.01 mol/L of NaOH (w/v) and 20% of ethanol (v/v) could regenerate the resins completely and the resins exhibited good reusability.