Ethyl alcohol (ethanol) is viewed upon as a fuel additive or even as an alternative fuel. Fermentation is used to produce dilute (<20 mass%) ethanol. This is needed to be concentrated to almost anhydrous, fuel grade ethanol (>99.5 mass%). The technologies used for concentration from dilute grade to fuel grade ethanol are summarized in this review. Thus, extraction; distillation; use of membranes; adsorption and some miscellaneous methods are discussed in detail. For each technique, the inlet and outlet concentrations; merits and demerits and scope for future work are indicated. Hybrid separations are discussed. In addition to technical feasibility, economic viability of the techniques is also discussed. A brief discussion on current industrial practice is also presented.

中文翻译：

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稀水溶液中乙醇的分离纯化技术综述

乙醇（乙醇）被视为一种燃料添加剂，甚至被视为一种替代燃料。发酵用于生产稀释（<20 质量%）乙醇。这需要浓缩成几乎无水的燃料级乙醇（>99.5 质量%）。本综述总结了从稀乙醇到燃料乙醇的浓缩技术。因此，提取；蒸馏；使用膜；详细讨论了吸附和一些杂项方法。对于每种技术，入口和出口浓度；指出了优缺点和今后的工作范围。讨论了混合分离。除了技术可行性外，还讨论了这些技术的经济可行性。还简要讨论了当前的工业实践。