Search

A series of novel L-malic acid modified hyper-cross-linked resins were synthesized from macroporous chloromethylated styrene-divinylbenzene copolymer by Fridel–Crafts reaction and esterification reaction. The adsorption behavior of the resin toward p-aminobenzoic acid was investigated from aqueous solution. KZ-3 displayed the most outstanding adsorption capacity due to its proper surface structure and higher functional group utilization rate. Subsequently, the adsorption kinetic of p-aminobenzoic acid onto precursor resin Z-3, modified resin KZ-3 and commercially available polymeric adsorbent H-103 was compared. The result demonstrated that KZ-3 had the optimal adsorption capacity because of its hydrogen bonding driving force and hydrophilicity enhancement which brought by oxygen-containing functional groups. Especially, KZ-3 is 3 times higher than the precursor resin in terms of adsorption rate. Kinetic curves could be characterized by pseudo-second-order rate equation and both the intra-particle diffusion and the film diffusion were the rate-limiting steps. The isotherms could be fitted by Langmuir model and the adsorption was an exothermic, spontaneous and more ordered arrangement process due to its negative thermodynamic parameters. [ABSTRACT FROM AUTHOR]