Quick
Search: 		  
advanced search
 GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help 
Clays and Clay Minerals Email Content Delivery
JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Clays and Clay Minerals; June 2006; v. 54; no. 3; p. 402-407; DOI: 10.1346/CCMN.2006.0540311
© 2006 Clay Minerals Society
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Rakhmatkariev, G.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation

MECHANISM OF ADSORPTION OF WATER VAPOR BY MUSCOVITE: A MODEL BASED ON ADSORPTION CALORIMETRY

Gairat Rakhmatkariev*

Institute of General and Inorganic Chemistry, Academy of Sciences of Uzbekistan, 77a, Kh. Abdullaev Ave., 700170 Tashkent, Uzbekistan

* E-mail address of corresponding author: gairat{at}chem.ccc.uz

Adsorption isotherms and differential heats of adsorption of water vapor by muscovite were measured at 303 K. The heats of adsorption are stepwise and each step corresponds to the stoichiometric formation of adsorption complexes of H2O molecules with K+ ions, (H2O)n/K+, (n = 1–6), which are located on the basal and lateral (edge) faces. At saturation, the ditrigonal cavities of the basal faces are fully occupied by hexameric clusters. It is suggested that half of the K+ ions on the basal faces come from neighboring layers by migration under the influence of the adsorbed H2O at the initial stage of adsorption. Similar migration of K+ to the edges was also hypothesized, suggesting that only every second site can be occupied by a cluster. At the final stage of adsorption, H2O molecules are believed to form H-bonded bridges between the hexameric water/cation clusters on the basal faces, whereas on the edge faces no such effect is believed to occur. The mean molar integral adsorption entropy of water is ~–7 J/mol K less than the molar entropy of the bulk liquid. The mobility of H2O on muscovite is slightly less than in bulk water. Migration of K+ cations under the influence of adsorbed H2O both on the basal and lateral faces of muscovite is reversible.

Key Words: Heats of Adsorption • Isotherm • Muscovite • Potassium Ion • Water Vapor






JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2008 by Clay Minerals Society