Infrared Studies of 1-Hexene Adsorbed onto Cr3+-Exchanged Montmorillonite

John M. Adams and Terry V. Clapp
Edward Davies Chemical Laboratories, University College of Wales Aberystwyth, Dyfed SY23 1NE United Kingdom

Abstract: When 1-hexene was adsorbed by Cr3+-montmorillonite at room temperature, all evidence of C=C(str) vibrations was lost. Protonation of the alkene occurred, and the secondary carbocation formed was bound at a site on the primary coordination sphere of the interlayer cation. Some of the hydrogen atoms of these primary-sphere water molecules were involved in strong hydrogen bonds to the silicate sheets, whereas others did not form such bonds, but were free and directed into the interlayer space. These latter hydrogen atoms were labile and protonated the alkene molecules.

Key Words: Adsorption • Alkene • Catalysis • Chromium • Hexene • Infrared spectroscopy • Water

Clays and Clay Minerals; February 1985 v. 33; no. 1; p. 15-20; DOI: 10.1346/CCMN.1985.0330102
© 1985, The Clay Minerals Society
Clay Minerals Society (www.clays.org)