Microwave-induced film evaporation separation process has been reported recently to separate the polar/nonpolar mixture. However, the efficiency of the separation is still too low for practical applications, which requires further enhancement via different strategies such as optimization design of evaporator structure. In addition the depth understanding of the separation mechanisms is great importance for better utilization of the microwave-induced separation process. To carry out these investigations, a novel microwave-induced falling film evaporation instrument was developed in this paper. The improvement of the enhancement effect of microwave-induced separation was observed based on the improved film evaporator. The systematic experiments on microwave-induced separation with different binary azeotropic mixtures (ethanol-ethyl acetate system and dimethyl carbonate (DMC)-H₂O system) were conducted based on the new evaporator. For the ethanol-ethyl acetate system, microwave irradiation shifted the direction of evaporation separation at higher ethanol content in the starting liquid mixture. Moreover, for DMC-H₂O system microwave-induced separation process broke through the limitations of the traditional distillation process. The results clearly demonstrated the microwave-induced evaporation separation process could be commendably applied to the separation of binary azeotrope with different dielectric properties. Effects of operating parameters are also investigated to trigger further mechanism understanding on the microwave-induced separation process.

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最近已经报道了微波诱导的膜蒸发分离方法来分离极性/非极性混合物。然而，分离的效率对于实际应用仍然太低，这需要通过诸如蒸发器结构的优化设计之类的不同策略来进一步增强。另外，对分离机理的深入理解对于更好地利用微波诱导的分离过程非常重要。为了进行这些研究，本文开发了一种新型的微波诱导的降膜蒸发仪。在改进的薄膜蒸发器的基础上，观察到了微波诱导分离增强效果的改善。₂ O系统）是基于新的蒸发器进行的。对于乙醇-乙酸乙酯系统，微波辐射使起始液体混合物中乙醇含量较高时蒸发分离的方向发生变化。而且，对于DMC-H ₂ O系统，微波诱导的分离工艺突破了传统蒸馏工艺的局限性。结果清楚地表明，微波诱导的蒸发分离工艺可用于分离具有不同介电性质的二元共沸物。还研究了操作参数的影响，以引发对微波诱导的分离过程的进一步机理的了解。

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