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A Cu-based catalyst, a developable catalyst in the acetylene hydrochlorination reaction, suffers from severe insufficient activity due to the reduction of Cun+sites under a C2H2atmosphere. In this work, we have developed a doped support strategy to maintain more than 90% of Cun+sites during the reaction via simply treating the mixture of melamine pyrophosphate and pristine activated carbon. Doped engineering for support plays dual positive roles in the acetylene hydrochlorination reaction: due to the interaction between Cu and doped sites, reduced C2H2molecules are easily desorbed at lower temperatures on the Cu sites to inhibit the reduction from Cun+to Cu0during the reaction. Besides, element-doped sites also provide more adsorption sites for reactant molecules to decrease the internal diffusion distance. Based on the above benefits, the optimal catalyst (Cu/N,P1/2-AC) achieved an initial C2H2conversion of 97.8%, and the activity loss of the catalyst was only 14.2% in the long-term stability test at 200 h. Finally, this strategy is extended by other two doped precursors with obvious catalytic performance enhancement. This designed strategy for Cu-based catalysts provides a new appreciation for the acetylene hydrochlorination reaction.

Co-free Ni-rich layered oxide cathodes need urgent development due to the continuously increasing demand for high-performance lithium-ion batteries. Here, the cathode materials of LiNi0.60Mn0.40O2(NM) and Fe-doped LiNi0.60Mn0.40–xFexO2(NMFe, x= 0.01–0.05) were prepared via a coprecipitation method associated with a high shear mixer, and the corresponding electrochemical performance was assessed. The optimal Fe-doped sample (NMFe-3) exhibits a discharge capacity of 185.3 mAh·g–1(0.1C), higher than that of NM (182.5 mAh·g–1) at 2.8–4.5 V and 25 °C. Characterization based on XRD, XPS, HRTEM, EIS, CV, and GITT tests illustrates the presence of LiFeO2crystal planes inside the NMFe samples, the lower values of the electrode/electrolyte interface impedance of the Fe-doped samples, and the charge-transfer impedance of the electrodes, as well as higher Li+diffusion rate during charge/discharge processes. In situ XRD tests confirm that NMFe-3 exhibits excellent reversible phase transition during the charge/discharge process. DFT calculations disclose that Fe dopants would make Li layer spacings enlarged and lower the energy barrier of Li+diffusion. This work provides a facile route to synthesize Fe-substituted Co-free Ni-rich cathode materials with excellent electrochemical performance for lithium-ion batteries.

To enhance oil–water separation efficiency, it is urgent to synthesize novel membrane materials that exhibit high flux and high retention efficiency and excellent antisolvent property. Herein, a seeding–extension–bud protrusion procedure was developed to fabricate superhydrophobic separation membranes through UV-assisted grafting and covalent modification on a microporous polypropylene. The synthesized superhydrophobic membranes (PPN-HDI-TPFOS) exhibit a bud protrusion micro/nanostructure, which significantly increases the contact area between the membrane surface and the emulsion, as well as the collision among the emulsion droplets during the oil–water separation. This membrane shows high flux of up to 24 800 L m–2h–1for dichloromethane (DCM)/water immiscible oil–water mixtures and 6528 L m–2h–1for water-in-DCM emulsions, together with excellent water retention (>99%) as well as good antisolvent property. Moreover, it exhibits excellent retention rates (>98%) for other water-in-oil emulsions (kerosene, hexane, and cyclohexane). This work supplies a useful strategy to synthesize complex membrane with extremely high flux as well as high rejection rate.

A series of stators were designed with the same opening area but different opening shape and number for the inline single-row blade-screen high shear mixers (HSMs), to study the emulsification and extraction, respectively. The opening number has a significant influence on the emulsification and extraction, as compared to the opening shape. The computational fluid dynamics (CFD) analysis was used to disclose the intensifying rules of HSMs with desirable stator geometry. In the rotor and screen region, both energy dissipation rate and shear stress increase first but then decrease as the opening number rises, whereas in the jet region both of them decrease with the opening number. The opening number can affect the flux through screen and shear gap, as well as the reentrainment and jet behaviors in the screen region. These results provide important guidance on the design and optimization of HSMs structures to intensify the emulsification and extraction.

Cu(II)Cu(I)/activated carbon (AC) catalysts with different copper chloride and cuprous chloride impregnation orders were prepared. The effect of the Cu(II) additive on the catalytic performance of Cu(I)/AC catalysts for gas–solid acetylene dimerization was evaluated. The optimal catalytic performance was obtained using the Cu(II)0.3Cu(I)1/AC catalyst with an average acetylene conversion of 70.0%. This value was an increase of 33.0% compared to the average acetylene conversion of 37.0% (Cu(I)1/AC) under the same reaction conditions. The results from the characterization of the Cu(II)Cu(I)/AC catalysts demonstrated that the addition of Cu(II) increased the dispersion of copper and inhibited copper loss on the catalysts. Consequently, our findings indicate that a suitable Cu+/Cu2+molar ratio improves the catalytic performance and stability.