(459f) Vapor Phase Separation of Water/Acetic Acid Mixtures through Mordenite Type Zeolite Membrane
AIChE Annual Meeting
2009
2009 Annual Meeting
Separations Division
Hybrid and Emerging Membrane Based Separations Technologies II
Wednesday, November 11, 2009 - 5:20pm to 5:45pm
The aqueous solution of acetic acid (AcOH) is by-produced in many chemical processes and reuse of AcOH requires de-watering of the AcOH aqueous solution. However, separation of water/AcOH mixtures by distillation consumes a large amount of energy due to the low relative volatility of water and AcOH. Combination of a membrane separation unit with distillation one can drastically reduce energy demand for the dehydration of acetic acid. While this system requires vapor phase separation of water/acetic acid mixture, there have so far been few studies on membrane separation under these conditions.
Mordenite is a kind of zeolites with both high stability and hydrophilic nature. In this communication, we report vapor phase separation properties of water/AcOH mixture through a mordenite type zeolite membrane.
A mordenite membranes was prepared on the outer surface of tubular porous a alumina support by a secondary-growth method, following the procedure described elsewhere [1]. Vapor permeation and separation measurements were performed using a stainless steel tube module cell. The effective membrane area was 6.28 cm2.
The mordenite membrane highly separated steam from water/AcOH mixtures. In the case of an equimolar mixture of water/AcOH (10/10 kPa), the permeances of water was 1.4 x 10-7 mol m-2 s-1 Pa-1 and the separation factor of water/AcOH exceeded 1000 at steady state at 448 K. The separation mechanism will be discussed.
[1] K. Sawamura et al., J. Chem. Eng. Jpn., 41 (2008) 870-877.
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