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Methyl acetate is a very important green solvent, which is often produced by esterification using excess methanol as one of the reagents. Therefore, costefficient separation of the methyl acetate/methanol mixture is important. However, the formation of a methanol/methyl acetate azeotrope at atmospheric pressure results in high energy consumption for their separation using distillation such as extractive distillation. In order to reduce the energy consumption, pervaporation (PV) was used to replace the distillation in this study. Two membranes, polydimethylsiloxane and polyoctylmethylsiloxane, were first compared in the PV separation of the methyl acetate/methanol mixture. Then the effects of different operating parameters such as temperature, feed flow rate, permeate pressure, and so on were investigated. Total flux was up to 100 kg/(m 2 ·hr) at 50°C, whereas the separation factor ranges from 1.2 to 5.0.Results showed that the methyl acetate/methanol azeotrope could be broken in the studied concentration range and high flux could be obtained. Furthermore, the change of activation energy with feed methyl acetate concentration and membrane thickness with temperature was investigated. To demonstrate the potential of the industrial applications, the stability in separation of 32 wt.% methyl acetate-methanol mixtures for 15 days was investigated. ORCIDWanqin Jin https://orcid.org/0000-0001-8103-4883 FIGURE 15 Membrane stability in the PV of 32 wt.% methyl acetate-methanol mixture at 25°C FIGURE 14Effects of downstream pressure on separation factor and total flux at 20°C and a fixed flow rate of 1,000 ml/min 10 of 12 LI ET AL.

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Bi 2 O 3 @ZnO sphere is prepared by solvothermal and proposed as an anode material for Zn-Ni battery, which shows a high discharge specific capacity and cyclic stability. The discharge specific capacity remains at a high level of 608.6 mAh g −1 after cycling 160 cycles at 1 C and the average specific capacity is up to 604.9 mAh g −1 , which is more excellent than pure ZnO. This striking property is attributed to the homogeneous distribution of Bi 2 O 3 in Bi 2 O 3 @ZnO sphere, which can improve the modification effects of Bi in the composites, exhibiting a better electrochemical reversibility.