An Ultraviolet Spectroscopic Method for Monitoring Surface Acidity of Clay Minerals under Varying Water Content

George W. Bailey and S. W. Karickhoff
National Environmental Research Center-Corvallis, Southeast Environmental Research Laboratory, U.S. Environmental Protection Agency, Athens, Georgia 30601, U.S.A.

Abstract: The ability of a clay mineral surface to function as an acid is not represented by bulk pH measurements. A method using u.v. analysis and organic indicators has been developed to monitor surface acidity. The u.v. organic indicator method enables sensitive in situ quantification of surface-induced protonation in wet or dry clay systems. The clay preparation procedure used yields reproducible acidic behavior.

Clays and Clay Minerals; December 1973 v. 21; no. 6; p. 471-477; DOI: 10.1346/CCMN.1973.0210607
© 1973, The Clay Minerals Society
Clay Minerals Society (www.clays.org)