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Selective separation of tocopherol homologues was performed by liquid-liquid extraction, using ionic liquids (ILs) as extractants in the presence of diluent. The distribution coefficients and selectivities of tocopherols in the biphasic system were determined. A selectivity of δ-tocopherol to R-tocopherol up to 21.3 was achieved when using [bmim]Cl as extractant diluted by methanol. Considering the structural differences of tocopherols, the separation mechanism based on the hydrogen-bonding interaction between IL's anion and the -OH group on the tocopherols was proposed. The separation efficiency of IL was greatly affected by its anion, and followed the order [bmim]BF 4 < [bmim]CF 3 SO 3 < [bmim]Cl under the same conditions, which is consistent with the ascending order of IL's hydrogen-bond basicity strengths.

Organic near infrared (NIR) persistent‐luminescence systems with bright and long‐lived emission are highly valuable for applications in communication, imaging, and sensors. However, realizing these materials (especially lifetime over 0.1 s) is a challenge, mainly because of non‐radiative quenching of their long‐lived excitons. Herein, a universal strategy of stepwise Förster resonance energy transfer (FRET) for a bright NIR system with remarkable persistent luminescence (up to 0.2 s at 810 nm) is presented, based on a new triphenylene‐dye‐doped polymer (triphenylene‐2‐ylboronic acid@poly(vinyl alcohol) (TP@PVA)) with a persistent blue phosphorescence of 3.29 s. This persistent NIR luminescence is demonstrated for application not only in NIR anti‐counterfeiting but also NIR bioimaging with penetrating a piece of skin as thick as 2.0 mm. By co‐doping a red dye (such as Nile red) and an NIR dye Cyanine 7 (Cy7) into this doped PVA film, the shortage of spectral overlap between TP emission and Cy7 absorbance is successfully solved, through a stepwise FRET process involving triplet to singlet (TS)‐FRET from TP to the intermediate red dye and then singlet to singlet (SS)‐FRET to Cy7. It is noted that the efficiency of the upper TS‐FRET is enhanced significantly by the lower SS‐FRET, leading to high efficiencies for the continuous FRETs.

Reaction rates, product distributions, and catalyst deactivation are reported for SAPO-34, MgO, MoO 3 , and physical blends of these materials in fixed-bed reactors. Methanol is converted to small olefins (C2 and C3 primarily) over SAPO-34. A small fraction of the methanol oligomerizes further, forming coke that deactivates the catalyst. Methanol is dehydrogenated to CO and H 2 over MgO catalysts. Methanol is oxidized to CO 2 over MoO 3 catalysts. Physically blending SAPO-34 with MgO or MoO 3 reduces the reaction selectivity for the methanol to olefins (MTO) reaction. Physical mixing of SAPO-34 and MgO favorably extends the catalyst lifetimes by reducing the rate of coke formation on SAPO-34. This is explained by opening up parallel reaction pathways involving oxygenated reaction intermediates. In contrast, SAPO-34 deactivation is more rapid when SAPO-34 is physically blended with MoO 3 . MgO by itself shows almost no catalytic activity for methanol. However, when MgO is sandwiched between layers of SAPO-34, the catalytic activity and production distribution from methanol is significantly altered to favor carbon oxides in comparison to SAPO-34 by itself. MgO is only catalytically active when it is sandwiched between layers of SAPO-34, demonstrating that reaction intermediates are transported from SAPO-34 to MgO and back again. Blends of MoO 3 and SAPO-34 showed that catalyst deactivation was more rapid in comparison to SAPO-34 alone; methanol was oxidized to formaldehyde over MoO 3 , which was transported to SAPO-34, where the acidic SAPO-34 catalyst is assumed to polymerize the formaldehyde. The data indicate that acid-catalyzed reactions critical to MTO, oligomerization, and scission reactions occur on SAPO-34. MgO-catalyzed methanol dehydrogenation and MoO 3 -catalyzed methanol oxidation. Physical blends of catalysts can open up new reaction pathways through coupling of different catalyst functionalities that may provide a simple and convenient method for tuning catalytic performance.

The technologies of ionic-liquid-mediated extraction have shown the good prospects for replacing traditional methods for separating natural bioactive homologues. However, so far, the roles and interactions of the anions and cations in the extraction process are not clear, which seriously hinders the further exploration of this new extraction technology. In this work, we report a detailed computational study, combined with experiment, on the interactions and hydrogen bonds between 1-butyl-3-methylimidazlium hexafluorophosphate ([Bmim][PF6]) ionic liquid (IL) and natural bioactive homologues, namely, three soybean isoflavone aglycones as model compounds. The distribution coefficients, D, of the three aglycones were experimentally determined in the [Bmim][PF6]–water biphasic system, and the order was found to be genistein (182.6) > daidzein (51.4) > glycitein (41.9). In DFT calculations, the lowest-energy complexes were obtained, and it was found that H-bonds are explicit intermolecular interactions in these complexes and that the IL can recognize these similar homologues by forming different H-bonds with the phenolic hydroxyls of aglycones. Furthermore, we found that the anions play a more important role in recognition than the cations. Subsequently, results of molecular dynamics (MD) simulations exhibited a good match with the structures of the isolated complexes calculated by DFT and also discovered that H-bonds were the main interactions between the anions and the phenolic hydroxyls in the first solvation shell.

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The separation of a compound of interest from its structurally similar homologues is an important and challenging problem in producing high-purity natural products, such as the separation of genistein from other soybean isoflavone aglycone (SIA) homologues. The present work provided a novel method for separating genistein from its structurally similar homologues by ionic liquid (IL)-based liquid-liquid extraction using hydrophobic IL-water or hydrophilic IL/water-ethyl acetate biphasic systems. Factors that influence the distribution equilibrium of SIAs, including the structure and concentration of IL, pH value of the aqueous phase, and temperature, were investigated. Adequate distribution coefficients and selectivities over 7.0 were achieved with hydrophilic IL/water-ethyl acetate biphasic system. Through a laboratory-scale simulation of fractional extraction process containing four extraction stages and four scrubbing stages, genistein was separated from the SIA homologues with a purity of 95.3% and a recovery >90%.