Mussel-Inspired Membrane Adsorber with Thiol Ligand for Patulin Removal: Adsorption and Regeneration Behaviors

Mussel-inspired membrane adsorber with thiol ligand (SH-membrane adsorber) is prepared by polydopamine-assisted poly(ethylene imine) grafting and subsequent thiolation modification for efficient removal of patulin. The effects of temperature, contact time, pH, and initial patulin concentration on the adsorption capacity of the membrane adsorber are investigated. The results show that the SH-membrane adsorber is effective to remove patulin. The adsorption capacity of the membrane can reach 1245.11 mu g g(-1) for patulin. In static adsorption tests, the adsorption kinetic and equilibrium data are well fitted by the pseudo-second-order kinetic model and Freundlich isotherm model, respectively, meaning that the adsorption process is a multilayer chemical adsorption. The SH-membrane adsorber can be recovered by l-cysteine, and the removal efficiency of patulin is maintained at about 89.23% after eight reuse cycles, compared to the 17.33% of control membrane. These results demonstrate that the SH-membrane adsorber has a potential application for patulin removal.