Novel magnetic carboxyl modified hypercrosslinked resins for effective removal of typical PPCPs

A series of novel magnetic carboxyl modified hypercrosslinked resins were successfully prepared via a sequence of suspension polymerization, hydrolysis and post-crosslinking reactions. The serial resins possessed both high cation exchange capacity and high specific surface area with MA-10 having the supreme specific surface area of 1238.65 m²/g and MA-70 having the largest exchange capacity of 6.45 mmol/g. The serial resins exhibited excellent adsorption capacity of typical PPCPs including chloramphenicol, atenolol, ibuprofen and tetracycline, which were neutral, cationic, anionic and zwitterionic respectively in natural water. The adsorption of chloramphenicol and ibuprofen was dominated by the hydrophobic and π-π Electron-Donor-Acceptor (EDA) interactions, while as to atenolol, the electrostatic interaction dominated the adsorption process. Especially, MA-50 was found to have the largest adsorption amount and the longest equilibrium time of zwitterionic tetracycline compared with other resins, the mechanism of which needed further investigation. Breakthrough tests showed that the serial resins had significant advantages over granular activated carbon F400D in contaminants removal for all of the four target pharmaceuticals. Batch experiments proved that the serial resins possessed strong anti-pollution ability and excellent regeneration property, which made it possible for the practical application in future water treatment.