Poly[1-vinyl-3-benzyltriethylammonium proline ionic liquid] membrane: Preparation, properties and adsorption applications

A novel poly[1-vinyl-3-benzyltriethylammonium proline ionic liquid] membrane(PIL/PVDF membrane) were prepared through the blending poly[1-vinyl-3-benzyltriethylammonium proline ionic liquid](P[Pro][TEA])-poly(vinylidene fluoride)(PVDF) phase inversion method. A series of PIL/PVDF membrane characterization (NMR, FT-IR, SEM, EDS, and XPS) was performed. The properties of PIL/PVDF membrane (contact angle, water flux, mechanical properties, thermal stability,electric charge property, specific surface area and pore diameter) were evaluated. A solid phase extraction − high performance liquid chromatography (SPE-HPLC) method for separation/analysis of quercetin was developed. The factors affecting the adsorption and elution (time, dosage, pH etc.) were investigated. Under optimal conditions, the method has been successfully applied to the separation/analysis of quercetin in tea, and the recovery rates are satisfactory (86.4–106.0 %). The concentration factor of quercetin was 10. The adsorption capacity of PIL/PVDF membrane towards quercetin was 22.1 mg g −1 . The extraction mechanism was preliminarily discussed. The established SPE-HPLC method was simple and reliable, which provided application prospects for extraction and detection of quercetin.