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Present anion exchange membranes are generally constructed by simple and positively charged polymers with insufficient organic solvent resistance, and exhibit a low selectivity in the separation of anions. Here, dissolving poly­(paraphenylene terephthalamide) nanofibers into small nanofibers and performing a reaction with quaternary ammonium groups in the one-dimensional small nanofibers, high-performance anion exchange membranes were successfully fabricated. By increasing the 2,3-epoxypropyl trimethylammonium chloride content, the synthesized amide nanofiber quaternary ammonium membranes (ANF#QA) exhibited a higher anion exchange capacity (as high as 1.75 mmol·g–1) and achieved a high electrochemical performance. In electrodialysis, the ANF#QA-10 membrane showed an exceptional Cl– selectivity in dilute and concentrated cells. Due to the dense structure and presence of carboxyl groups on the nanofibers, the ANF#QA membranes exhibited a selective separation of monovalent anions. After 48 h of immersion in aqueous acetone solutions, the final ANF#QA-10 membrane exhibited high desalination and concentration efficiency as the initial membrane. This work highlights the promising use of positive charges on small nanofibers, and proposes the design of a special anion exchange membrane, which can be used for electrodialysis in organic solvent solutions, and to selectively separate monovalent anions.

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Nonsulfided CeO2‐supported different metal catalysts were synthesized, characterized and evaluated in the hydrogenation of octanoic acid with a batch reactor at the temperature of 280 oC and initial H2 pressure of 3 MPa. The effect of Mo species was revealed by comparing Mo‐doped catalysts with Mo‐free catalysts. The catalytic results show that the CeO2 supported Ni catalyst doped with Mo exhibit much higher catalytic activity and octane selectivity than the catalysts without dopants. Additionally, the influences of Mo and Ni mass ratio on the conversion of octanoic acid and the selectivity of heptane and octane over CeO2‐based catalysts were also discussed. Ni species seemed beneficial for the deoxygenation reaction to form C7 alkane, while the doping of Mo favored the hydrodeoxygenation path to C8 alkane via dehydration‐hydrogenation of the octanol intermediate.