Department of Chemical Engineering, Inha University, Incheon 402-751, South Korea.
Appl Biochem Biotechnol. 2013 Feb;169(3):1056-68. doi: 10.1007/s12010-012-0076-z. Epub 2013 Jan 9.
Bioethanol is considered a potential liquid fuel that can be produced from biomass by fermentation and distillation. Although most of the water is removed by distillation, the purity of ethanol is limited to 95-96 % due to the formation of a low-boiling point, water-ethanol azeotrope. To improve the use of ethanol as a fuel, many methods, such as dehydration, have been proposed to avoid distillation and improve the energy efficiency of extraction. Glucose-based silica, as an adsorbent, was prepared using a simple method, and was proposed for the adsorption of water from water-ethanol mixtures. After adsorption using 0.4 g of adsorbent for 3 h, the initial water concentration of 20 % (water, v/v) was decreased to 10 % (water, v/v). For water concentrations less than 5 % (water, v/v), the adsorbent could concentrate ethanol to 99 % (ethanol, v/v). The Langmuir isotherms used to describe the adsorption of water on an adsorbent showed a correlation coefficient of 0.94. The separation factor of the adsorbent also decreased with decreasing concentration of water in solution.
生物乙醇被认为是一种有潜力的液体燃料，可以通过发酵和蒸馏从生物质中生产。尽管蒸馏过程中大部分水分都被去除了，但由于形成了低沸点、含水乙醇共沸物，乙醇的纯度只能达到 95-96%。为了提高乙醇作为燃料的使用效率，已经提出了许多方法，如脱水，以避免蒸馏并提高提取的能源效率。葡萄糖基硅胶作为一种吸附剂，采用简单的方法制备，并被提议用于从水-乙醇混合物中吸附水。使用 0.4 g 吸附剂吸附 3 小时后，将初始水浓度 20%（水，体积比）降低至 10%（水，体积比）。对于水浓度小于 5%（水，体积比）的情况，吸附剂可以将乙醇浓缩至 99%（乙醇，体积比）。用于描述水在吸附剂上吸附的朗缪尔等温线的相关系数为 0.94。吸附剂的分离因子也随溶液中水浓度的降低而降低。
