Very high flux MFI membranes for alcohol recovery via pervaporation at high temperature and pressure

التفاصيل البيبلوغرافية
العنوان: Very high flux MFI membranes for alcohol recovery via pervaporation at high temperature and pressure
المؤلفون: Mattias Grahn, Liang Yu, Jonas Hedlund, Danil Korelskiy
المصدر: Separation and Purification Technology. 153:138-145
بيانات النشر: Elsevier BV, 2015.
سنة النشر: 2015
مصطلحات موضوعية: Pressure drop, Membrane, Chromatography, Aqueous solution, Chemical engineering, Atmospheric pressure, Chemistry, Filtration and Separation, Fugacity, Pervaporation, Partial pressure, Permeation, Analytical Chemistry
الوصف: Ultra-thin MFI membranes (0.5 μm) were evaluated for recovery of alcohols from dilute aqueous mixtures by pervaporation at high temperature and pressure for the first time. The feed pressure was sufficiently high to keep the feed in liquid state at high temperature, while the permeate pressure was kept at atmospheric and a low flow of sweep gas was used to reduce the partial pressure on the permeate side. Atmospheric pressure on the permeate side is more practical than vacuum. High feed temperature and pressure result in high fugacity in the liquid feed, which, in combination with lower permeate pressure, results in a large driving force. Consequently, the membrane exhibited very high fluxes for feeds comprised of 10 wt% ethanol/water and 5 wt% n-butanol/water mixtures at 110 °C and 140 °C, respectively. The flux observed for 10 wt% ethanol/water mixtures was as high as about 52 kg m−2 h−1, i.e., 6 times higher than the highest previously reported flux for this separation using zeolite membranes in pervaporation. For 5 wt% n-butanol/water mixtures, the flux was 40 kg m−2 h−1, which is 11 times higher than the highest previously reported flux for this separation by zeolite membranes. At these conditions, the membrane displayed separation factors for ethanol/water and n-butanol/water mixtures of 5 and 16, respectively. However, after about 6 h of operation, the separation factor decreased significantly and the flux increased due to formation of defects in the membrane when the feed was saturated with silica. Lower membrane stability was observed for silica free feeds. The work has shown that it is possible to obtain high flux in pervaporation by using ultra-thin membranes in combination with high feed temperature. The observed membrane selectivity was not excellent, due to pressure drop over the support as well as likely concentration polarisation on the feed side resulting from the high flux. Membrane stability was also an issue at these conditions, however it was shown that stability could be improved by saturating the feed with silica.
تدمد: 1383-5866
DOI: 10.1016/j.seppur.2015.09.005
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_________::967ed168b53dfd933399e2a905f86214
https://doi.org/10.1016/j.seppur.2015.09.005
Rights: CLOSED
رقم الانضمام: edsair.doi...........967ed168b53dfd933399e2a905f86214
قاعدة البيانات: OpenAIRE
الوصف
تدمد:13835866
DOI:10.1016/j.seppur.2015.09.005