(584d) Development of Zeolite Membranes for Dehydration Under High-Water Conditions and Acidic Conditions | AIChE

(584d) Development of Zeolite Membranes for Dehydration Under High-Water Conditions and Acidic Conditions

Authors 

Sato, K. - Presenter, Mitsubishi Chemical Corporation
Sugimoto, K. - Presenter, Mitsubishi Chemical Corporation
Kyotani, T. - Presenter, Mitsubishi Chemical Corporation
Shimotsuma, N. - Presenter, Mitsubishi Chemical Corporation


The application of zeolite membranes to dehydration process has been realized for ten years with the LTA type membrane [1], followed by many studies to develop the higher permeating fluxes and practical fabrication methods [e.g., 2] and by technologies of vapour permeation (VP) in an ethanol producing plant [3]. It is known, however, that LTA membrane can be applied to only neutral pH conditions because of the lack of resistance to acid. On the other hand, the potential market of separating membranes for dehydration under acidic conditions could be large, so that it has been expected that zeolite membranes with acidic resistance should be developed for industrial purpose. Scientific and practical studies have been reported [e.g.,4-7] that the mordenite membranes are such candidate that could be applied to dehydration under acidic conditions. In this background we prepared mordenite membranes to determine permeating properties in VP at higher temperatures and pressures up to 130゚C and 560 kPaA, corresponding to conditions in practical industrial process. Six samples of tubular mordenite membrane were treated simultaneously in hydrothermal synthesis at 180゚C on porous alumina substrate with 10cm long by seeded growth using synthetic solution with a composition of 10Na2O:0.3Al2O3:36SiO2:960H2O [7]. The quality of synthesized membranes was examined by pervaporation (PV) at 75゚C in a feed mixture of IPA(90wt.%)/water(10wt.%), resulting in fluxes of 0.72 kg/m2h in average (1-R=0.062) and separation factors () of 3100?5800 and showing high reproducibility. One of samples was applied to VP separation in the feed mixture and results are in Figure 1, showing the fluxes are increased with the increasing of temperature. The separation factors () were increased from  =470 at 130゚C to  =1600 at 100゚C. A preliminary VP experiment on a mordenite sample was carried out in a feed vapour mixture with composition of acetic acid (36wt.%)/water(64wt.%) at 110゚C, resulting in that flux was 1.9 kg/m2h and the leakage of acetic acid into the permeate water was 0.13wt.%. These results indicate that mordenite membranes have property to dehydrate IPA solvent and also hydrous acetic acid without lost of separating ability even at higher temperatures at 100-130゚C in VP, and further suggested that mordenite membranes synthesized by this fabrication method could be up-scaled and installed in practical industrial processes.

References [1] Y. Morigami, M. Kondo, A. Jun, K. Okamoto, Separation and Purification Technology, 25 (2001) 251. [2] K. Sato, T. Nakane, Journal of Membrane Science, 307, (2008) 181. [3] K. Sato et.al., Microporous and Mesoporous Materials, 115 (2008) 184. [4] K. Suzuki, Y. Kiyozumi, T. Sekine, K. Obata, Y. Shindo, S. Shin, Chemical Express, 5 (1990) 793 [5] G. Li, E. Kikuchi, M. Matsukata, Separation and Purification Technology, 32 (2003) 199. [6] A. Navajas, R. Mallada, C. Tellez, J. Coronas, M. Menendez, J. Santamaria, Journal of Membrane Science, 299, (2007) 166. [7] G. Li, E. Kikuchi, M. Matsukata, Microporous and Mesoporous Materials, 62 (2003) 211. This research is supported by NEDO (New Energy and Industrial Technology Development Organization, JAPAN)