Tuning of Delicate Host–Guest Interactions in Hydrated MIL‐53 and Functional Variants for Furfural Capture from Aqueous Solution

Abstract

Capture of high-boiling-point furfural from diluted aqueous solution is a critical but challenging step in sustainable bio-refinery processes, but conventional separation methods such as distillation and liquid-liquid extraction requires prohibitive energy consumption. We report control over the microenvironment of hydrated MIL-53 and isoreticular variants with diversified functional terephthalic acid linkers for the purpose of preferential binding of furfural through delicate host-guest interactions. Methyl-bounded MIL-53 with improved binding energy in the hydrated form results in highly efficient capture ratio (ca. 98 %) in the extremely low concentration of furfural solution (0.5-3 wt %) and 100 % furfural specificity over xylose. The distinct hydrogen bonding sites and multiple Van de Wall interactions for furfural adsorption was testified by computational modeling. Furthermore, the recovery ratio of furfural reaches ca. 93 % in desorption.

A LDH Template Triggers the Formation of a Highly Compact MIL‐53 Metal‐Organic Framework Membrane for Acid Upgrading

“…MIL‐53, on account of hydrophilicity, can spontaneously adsorb moisture in the air, as reflected by a slight thermal‐gravity (TG) variation coupled with mass spectra (MS), shown in Figure S21a. The tiny amount of water molecules can partially connect to the Al(−OOC) 2 or Al(−OH) units through H‐bonds or H‐bridge‐bonds reported in our previous study, [19] which gives rise to three signals in the 27 Al solid‐state magic‐angle spinning (MAS) nuclear magnetic resonance (NMR) spectrum (Figure 4d and e). The MIL‐53 powder was then soaked in the 90/10 AA/water hot solution to mimic the adsorption of components from the liquid feed in pervaporation (step 1).…”

Confinement effect and efficient adsorption of furfural onto ZIF‐8‐derived microporous carbon

“…3(b)]. 7,12,14,26,27 Figure 3(c), (d) show the static competitive adsorption experiments carried out for furfural-acetic acid mixtures on the porous C materials to understand the influence of pore structure on the adsorption process and its efficiency. The preference of NC ZIF-8 800C-800A and NC ZIF-8 1000C-800A toward furfural led to an outstanding furfural adsorption capacity in binary component competitive adsorption, which was consistent with the singlecomponent adsorption data.…”

“…Zeolitic imidazolate frameworks (ZIFs)‐derived porous carbon (C) materials are highly promising candidates when compared to previously reported adsorbents, including activated C, 6‐10 polymers 11‐13 and ZIFs 14‐17 . The excellent adsorption behavior lies in the tunable surface chemistry/pore structure of C and its π–π interactions with furfural 18 .…”

“…Zeolitic imidazolate frameworks (ZIFs)-derived porous carbon (C) materials are highly promising candidates when compared to previously reported adsorbents, including activated C, [6][7][8][9][10] polymers [11][12][13] and ZIFs. [14][15][16][17] The excellent adsorption behavior lies in the tunable surface chemistry/pore structure of C and its π-π interactions with furfural. 18 Our recent study demonstrated that furfural adsorption is closely related to the hydrophobicity, electrostatic interactions and π-π interactions of the adsorbent.…”