A novel tungsten-ion imprinted polymer prepared for selective adsorption and separation of tungsten and molybdenum

Due to the nearly identical physical and chemical properties of tungsten (W) and molybdenum (Mo), the efficient recycling of W-Mo resources remains a significant research challenge. In this work, a W ion imprinted polymer (W-IIP) was proposed for a more efficient and environmentally friendly W-Mo separation process. W-IIP was prepared by a bulk polymerization method with 4-vinylpyridine as monomer, W(Ⅵ) as ion template, and ethylene glycol dimethacrylate as crosslinker. Characterization by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, nitrogen adsorption–desorption isotherms, and thermogravimetry revealed that W-IIP possessed abundant pyridyl recognition sites, uniform particle structure, a large specific surface area, and good thermal stability. Through optimizing the adsorption conditions, the maximum separation coefficient β Mo W MAX reached 75, and an adsorption capacity Q W of 63.8 mg⋅g −1 was achieved at pH 4.5, a temperature of 75 ℃, and a time of 300 min. Based on the adsorption isotherms and kinetics fitting results, the adsorption process followed the pseudo-first-order kinetic model and the Langmuir model, and the adsorption of W was spontaneous monolayer surface adsorption. After five adsorption–desorption cycles, Q W remained at 92 %. The X-ray photoelectron spectroscopy characterization combined with the W-Mo-H 2 O thermodynamic diagram, suggested that the combination of the pyridine groups as recognition sites and the imprinted cavity of the W-IIP with tungstate may be the reason for the effective selective adsorption of W. Considering its excellent affinity and specific selectivity, W-IIP might evolve into a potential material for the separation of W and Mo although it faces limited recycling ability, cost implications and potential scalability constraints in the future. To address these limitations, future research could focus on developing new synthetic methods and optimizing the monomers to further enhance the overall performance of W-IIP.