Adsorption of Lower Alcohols from Water Solutions on High Silica Zeolites, Mesoporous MCM-41 and AlPO-5

• Main Authors: Ivar M. Dahl, Elisabeth Myhrvold, Åse Slagtern, Michael Stöcker
• Format: Article
• Language: English
• Published: Hindawi - SAGE Publishing 1997-04-01
• Series: Adsorption Science & Technology
• Online Access: https://doi.org/10.1177/026361749701500404

Two dealuminated β-zeolites, zeolite Y and MCM-22 as well as silicalite, MCM-41 and AlPO 4 -5 have been studied as hydrophobic adsorbents in water solutions. Dealuminated β-zeolite, MCM-22 and silicalite all adsorb alcohols from water solutions. Enhanced adsorption is obtained for alcohols with longer alkyl chains. Adsorption in the practically most interesting 10–80% range of zeolite filling may adequately be described by Langmuir isotherms. The Langmuir adsorption constants are similar for β-zeolite, MCM-22 and silicalite. This indicates that the adsorption is independent of the pore structure for the alcohols tested in this study. The surface silanol density is however important, such that a low SiOH density is required to give lipophilic properties. In line with this, dealuminated zeolite Y, as prepared here, and MCM-41 give only a poor preference for alcohols from water. For the β-zeolite, the dealumination procedure is important for retaining the micropore volume and adsorption capacity of the zeolite. AlPO 4 -5 shows no potential as an adsorbent for alcohols from water solutions.