| Lower alcohol (ethanol, isopropanol , n-propanol and so on)–water sysytem isthe most typical azeotrope. In this paper, ethanol-water separation by thermostatadsorptive distillation with a squeezed compound starchiness adsorbent——ZSG-1,which is novel, environmental and recoverable. Ethanol of 99.7wt% in purity isachieved in this method.And it is investigated both experimentallyand theoretically.First,corn and sweet potato are selected as the basic raw materials throughscreening. Then they are mixed, squeezed and joined the process of foaming agent toprepare an adsorbent. The hollowΦ3×3mm absorbent pieces, rich in microspore, isnamed ZSG-1,and passes a test under the pressure of 313kPa. The adsorbent absorbedwater strongly, with alcohols being screened out simultaneously. The purpose ofdehydration can reached during ethanol-water vapor flow through the adsorbent bed.The experiments are performed to measure the mass of adsorptive water andethanol, adsorptive breakthrough curves. It is shown that the sensitive factors for thevapor absorption process include the fixed bed temperature, the water concentration,and the superficial velocity. When all of the parameters were set at suitable value,higer capacityof water absorption would be attained.According to experimental the mass transfer rate constant of H2O to ZSG-1 is13.6 m3·kg(-1)·h-1 at 89℃. It is relatively small. At the same time, the adsorptioncapacity of ZSG-1 for H2O is 51.8 kg?m-3. Saturated capacity 0.1511g(H2O)/g, whichis close to the capacityof 3A zeolite.Inverse gas chromatography method is adopted in the research, indicating the netretention time of H2O for ZSG-1 is much larger than ethanol; the absorption heat ofZSG-1 for H2O (?Habs) is 3.16×104J·mol-1...
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