The development of efficient and low-cost strategy for production of monoethylene glycol (MEG) through hydration of ethylene oxide (EO) at low H2O/EO molar ratios is an important industrial challenge. We...

In this work, poly(ionic liquid)s (PILs) with swelling ability were prepared via the free radical copolymerization of N‐vinyl imidazolium ionic liquids and divinylbenzene. Nuclear magnetic resonance and Fourier‐transform infrared analyses confirmed the successful synthesis of PILs. The PILs were evaluated as demulsifiers for a model oil‐in‐water emulsion, where sodium dodecyl sulfate (SDS) was used as a surfactant. The demulsification efficiencies of PILs increased from 18%, 34%, 92% to 99% with the alkyl chain of three‐substituents on imidazolium varied from n‐octyl, n‐hex1yl, n‐butyl to n‐ethyl, which positively related with the swelling ratios of PILs in the emulsion. The amounts of dodecyl sulfate and Br− in the aqueous phase after demulsification were analyzed by high‐pressure liquid chromatography and ion chromatography, respectively. The decreased amount of dodecyl sulfate coincided with the increased amount of Br−, indicating that the anion exchange between surfactant SDS and PILs was occurred. The PILs could be recycled by ion exchange with NaBr solution and the demulsification efficiencies did not show significant decline during five times of recycling. Meanwhile, P[VEIm]Br@4 Å zeolite prepared by loading poly(1‐vinyl‐3‐ethylimidazolium bromide) on 4 Å zeolite was used for continuous demulsification in the T type device. The T type device had stable fluxes (1083 L ·m−2 h−1) for various oil‐in‐water emulsions with excellent demulsification efficiencies (above 99%).

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Swelling is a very common phenomenon in organic substances. However, the swelling behaviors of inorganic substances had rarely been reported. In this study, a new type of swellable organic–inorganic hybrid polymer (PIL@CHT) was designed and successfully synthesized through free-radical copolymerization of polymerizable phosphonium ionic liquid monomer and vinyl-functionalized hydrotalcite (CHT). The swelling behaviors of PIL@CHT in various solvents with a wide range of Hansen solubility parameters (δT) were investigated, and PIL@CHT exhibited excellent swellable capacity in the solvents with δT > 24.4 MPa1/2. The swollen state of the hybrid PIL@CHT in water presented a network structure with a diameter of approximately 8–12 μm, and CHT particles were well dispersed to the channel of PIL. PIL@CHT was applied to catalyze the CO2-assisted hydration of propylene oxide (PO), in which a cascade reaction including the cycloaddition of CO2 and PO and the subsequent hydrolysis of propylene carbonate (PC) occurred. PIL@CHT, combining the active sites of PIL and CHT, synergistically catalyzed this cascade reaction and achieved a high yield (93.0%) and selectivity (98.2%) of 1,2-propanediol (1,2-MPG) under a low H2O/PO ratio of 1.5/1. Moreover, the catalyst could be recycled seven times without any significant loss of catalytic activities and had good substrate generality.

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