In-situ construction of consecutive and selective transfer sites in microchannels of porous separation membrane

Excellent molecular selectivity and water transport property of molecularly imprinted membranes (MIMs) have shown application prospects in recovering phenolic compounds (PCs) from olive miller wastewater (OMW). The chemical structure of porous separation membranes for OMW treatment can guarantee their selectivity and operational stability. Herein, selective transfer sites are consecutively constructed in chitosan (CS) membrane microchannels using an in-situ growth strategy. Highly adhesive tannic acid (TA)/3-aminopropyltriethoxysiliane (APTES) nanoparticles, which exhibited the interaction with target molecules (kaempferol, KMF), controllably construct the precise imprinted sites in interpenetrating pores of membranes (E-KMIMs). E-KMIMs considerably enhanced the linked porosity structure and expand the number of continuous transfer sites possible within microchannels in comparison to coating on the outer membrane surface (S-KMIMs). Notably, E-KMIMs exhibited impressive imprinting factor (3.38) and relative separation factor (3.81), which were 55.92 % and 68.50 % higher than those of S-KMIMs, respectively, and 3.80 times that of non-imprinted membranes (NIMs). Moreover, the permselectivity coefficient (4.14) of E-KMIMs was 2.71 times higher than that of NIMs. Additionally, the average water permeability of E-KMIMs reached 1046.46 L m⁻² h⁻¹, representing a 44.72 % increase compared to S-KMIMs. The selective separation mechanism was elucidated through dynamic molecular computation and in-situ attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR) analysis. This facile methodology for developing highly effective and stable MIMs holds significant promise for advancing membrane separation technology towards sustainable development.