Water-stable metal−organic framework (MOF) UiO-66 was studied in boron removal from water for the first time. XRD, SEM, nitrogen adsorption/desorption isotherms, and thermogravimetric analysis (TG) were employed to confirm the structure. The boron adsorption kinetics, isotherms, thermodynamics, mechanism, and recycling on UiO-66 were further investigated in batch adsorption process. UiO-66 exhibits great adsorption performance of 10.59 mmol• g −1 at 45 °C, and the adsorption process reaches equilibrium rapidly in 1 h. Pseudo-second-order model, intraparticle diffusion, and Boyd model are employed for kinetic analysis. The process is a spontaneous endothermic process controlled by entropy change rather than enthalpy change, which suggests intensive chemisorption. The adsorption capacity does not decrease obviously after four cycles. Characterization on exhausted UiO-66 with 11 B MAS NMR reveals not solely interaction between boric acid and UiO-66. The XPS patterns suggest interaction with an Zr site, which is confirmed by the adsorption simulation with quantum chemistry. Higher boron adsorption capacity than conventional boron removal adsorbents and easy regeneration make UiO-66 a promising agent for boron removal from aqueous solution.

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In this work, seven metal–organic frameworks [ZIF-8, MIL-53­(Cr), MIL-96­(Al), MIL-100­(Cr), MIL-100­(Fe), MIL-101­(Cr), and UiO-66 ] were applied for adsorptive separation of fructose–glucose mixture. UiO-66 exhibited better performance in adsorption capacity and selective adsorption of fructose. The adsorptive process with UiO-66 was further investigated in detail including kinetic, isotherm, and adsorption mechanisms. The rate-determining step analysis based on film diffusion and intraparticle diffusion model suggested that the adsorption process was controlled by multiple steps, which fitted the pseudo-second-order model. The Freundlich model was fitting better than the Langmuir model, which indicated multilayer adsorption on heterogeneous surface. The thermodynamic parameters (ΔG, ΔH, and Δ S ) were calculated, indicating that adsorption process on UiO-66 was an endothermic and entropy increment process. UiO-66 can be a promising adsorbent for adsorptive separation of fructose and glucose.

The local microenvironment of single-atom electrocatalysts (SACs) governs their activity and selectivity. While previous studies have focused on the first coordination shell (FCS) of metal centers, functional species beyond FCS...