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[Display omitted] • Mesoporous polymer ionic liquids for the immobilization of lipase demonstrated mesoporous properties. • Resultant systems were used as recyclable biocatalysts for ester production. • Lipase immobilization led to higher stability than that of the free enzyme. • The process can generate high-purity esters using lipase-immobilized mesoporous polymer ionic liquid. Herein, fatty acid esters were synthesized cost-effectively from various fatty acids using reusable lipase (L) immobilized with novel porous ionic polymer (PIP) (l –PIP). The functionalized mesoporous PIP was synthesized through Friedel–Crafts alkylation reaction of 1, 4-bis(bromomethyl) benzene in the presence of ferric chloride as catalyst, and lipase was completely immobilized with PIP at varied time, forming l –PIP–6 H , l –PIP–12 H , l –PIP–18 H , l –PIP–24 H , l –PIP–30 H , and l –PIP–36 H , which were applied in ester production. l –PIP–30 H was characterized using FT–IR, SEM, XPS, solid–state 13C NMR, and N 2 adsorption–desorption isotherms. The conversion of oleic acid reached 88.21 % under optimized conditions (12:1 ethanol/oleic acid molar ratio after 5 h at 45 °C with 250 wt% catalyst at 300 rpm). The stability and reusability of l –PIP–30 H were demonstrated by the sustained catalytic efficiency for at least six reaction cycles. Good catalytic activity during the esterification of various free fatty acids with ethanol was observed. This cost–efficient and effective lipase–immobilized PIP catalyst may have positive economic and environmental repercussions to inspire further academic and industrial research on biodiesel. [ABSTRACT FROM AUTHOR]

Fixing the greenhouse gas CO2 through epoxide helps to mitigate worldwide ecological troubles. The applications of metal‐free and solvent‐free catalysts remain a challenge for CO2 catalytic conversion. In this work, an array of quaternary ammonium salts derived from polyethyleneimine with hydroxyl groups ([PEI‐GDMAB‐Cn]Br) were constructed by the reaction of branched PEI with a molecular weight of 10000 and glycidyl alkyl dimethylammonium bromide. A range of experiments were designed to demonstrate that [PEI‐GDMAB‐Cn]Br can be considered as a valid metal‐free and solvent‐free homogeneous catalyst for the CO2‐epoxide cycloaddition reaction. Among of [PEI‐GDMAB‐Cn]Br, [PEI‐GDMAB‐C18]Br catalyzed the model reaction of CO2 and epichlorohydrin under optimized reaction conditions (T=80 °C, 1.0 atm CO2, catalyst 1 mol%, ECH 15 mmol, 16 h) and the conversion achieved at 97.5 %. Moreover, the catalyst exhibited stable reusability and broad substrate applicability, which was used in the following cycle succinctly, because of self‐separated properties by temperature control. The [PEI‐GDMAB‐C18]Br catalyzed reaction process was detected as a pseudo‐first‐order reaction after kinetic studies and an Ea was calculated to be 50.65 kJ/mol. A combinatorial catalytic mechanism of hydrogen bonding and bromide ions is suggested to explain the remarkable catalytic performance of this bifunctional catalyst. [ABSTRACT FROM AUTHOR]

A series of carbon sphere supported with adjustable alkyl length substitutes polymeric ionic liquids bearing hydroxylamino-anchored functional groups by covalent connection were fabricated from copolymerization of carbon sphere with vinyl based monomeric ionic liquids, which were constructed from 1-glycidyl-3-vinylimidazolium bromide and alkyl amines. The carbon sphere hybrid polymeric ionic liquids were characterized by FT-IR, SEM–EDS, N2 adsorption/desorption isotherm, elemental analysis, 13C MAS NMR and XPS, which were candidated as heterogeneous catalysts for CO2-epoxide cycloaddition reactions to product cyclic carbonates at mild conditions without co-catalyst and metal ion. The introduced functional groups on carbon sphere could accelerate the reaction process and yields of above 90% were obtained for various cyclic carbonates under optimized conditions. Finally, kinetic experiments were also carried out to reveal reaction mechanism and the activated energy was determined as 114.9 kJ/mol. Therefore, this study provides a new approach to fabricate multifunctional heterogeneous materials for coupling reaction of CO2 under mild conditions. [ABSTRACT FROM AUTHOR]