A novel post-cross-linked polystyrene/polyacryldiethylenetriamine (PST_pc/PADETA) interpenetrating polymer networks (IPNs) and its adsorption towards salicylic acid from aqueous solutions

• A strategy to synthesize PST_pc/PADETA IPNs was proposed.
• PST_pc/PADETA IPNs had a large equilibrium capacity towards salicylic acid.
• Adsorption of salicylic acid on PST_pc/PADETA IPNs was a fast process.
• PST_pc/PADETA IPNs had a large dynamic capacity towards salicylic acid.
• Regeneration of PST_pc/PADETA IPNs was regenerated after the adsorption process.

We developed an effective strategy to synthesize a novel post-cross-linked polystyrene/polyacryldiethylenetriamine (PST_pc/PADETA) interpenetrating polymer networks (IPNs) for improving the adsorption of salicylic acid from aqueous solutions. PST_pc/PADETA IPNs was synthesized from polystyrene (PST) successfully and it possessed a very large equilibrium capacity towards salicylic acid, and the equilibrium capacity of salicylic acid on PST_pc/PADETA IPNs is about double relative to the precursor PST. The Freundlich model was more appropriate for fitting the equilibrium data than the Langmuir model, and the isosteric enthalpy decreased with increasing of the fractional loading. The pseudo-second-order rate equation could characterize the kinetic data and the micropore diffusion model could describe the kinetic data very well. At an initial concentration of 1003.6 mg/L and flow rate of 11.25 BV/h, the breakthrough and saturated capacities were measured to be 82.40 and 151.0 mg/mL wet resin, respectively, and the resin column could be completely regenerated and repeatedly used by 0.01 mol/L of sodium hydroxide (w/v) aqueous solutions.