Eco-friendly 2D boron nitride membranes with molecular imprinting for sustainable recovery of phenolic compounds

In this study, a sustainable and efficient strategy was developed to selectively recover phenolic compounds using a novel 2D hexagonal boron nitride (h-BN) molecularly imprinted membrane. The h-BN nanosheets were functionalized with tannic acid (TA), creating a hydrophilic microenvironment with expanded interlayer spacing that enhances water permeability and provides a conducive structure for target molecule recognition. Using green ionic liquids as functional monomer and crosslinker, selective binding sites for kaempferol (KMF) were created on the f-BN framework, yielding a KMF molecularly imprinted membrane (KMIMs) with exceptional selective adsorption and separation performance. KMIMs demonstrated high separation factors for KMF against structurally similar molecules (α = 3.99 for apigenin and α = 3.32 for quercetin) and superior permeability, balancing flux and selectivity for sustainable application. Spectral analysis, UV–Vis red-shift, and in-situ ATR-FTIR confirmed the binding interactions within the molecularly imprinted sites. The molecular dynamics simulation results further confirmed that the interaction between KMF and the imprinted sites was predominantly governed by hydrogen bonding and π-π stacking interactions. This approach offers a scalable and environmentally friendly solution for the recovery and valorization of bioactive compounds from wastewater, contributing to green and sustainable development.