HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Moore, D. E. Articles by Dixon, J. B. Search for Related Content PubMed Articles by Moore, D. E. Articles by Dixon, J. B. Agricola Articles by Moore, D. E. Articles by Dixon, J. B.

Glycerol Vapor Adsorption on Clay Minerals and Montmorillonitic Soil Clays¹

ABSTRACT

Adsorption isotherms of glycerol were obtained for clay fractions of montmorillonite, vermiculite, kaolinite, and eight soil clays at 80C in an evacuated system. The weight of glycerol required for monolayer formation was determined by application of the BET equation to adsorption data. Montmorillonite samples gave BET monolayer values from 211 to 230 mg glycerol/g of montmorillonite which is in the theoretical range. Monolayer values calculated for soil montmorillonites from BET monolayer values and corrected for impurities were 209 to 239 mg glycerol/g of montmorillonite in < 0.08µ soil clays. The surface area values estimated from these soil montmorillonite monolayer values range from 738 m²/g to 844 m²/g. Vermiculite gave BET monolayer values of 40 mg and 96 mg/g of clay for 2 to 0.2µ and 0.2 to 0.08µ samples, respectively. This method appears to effectively measure the sorption surface of montmorillonite and indicates lower sorption surface of vermiculite than is suggested by its structural similarity to montmorillonite. Glycerol monolayer values indicate only modest reduction of particle size in < 0.08µ compared to 0.2 to 0.08µ montmorillonite from soil clays and Wyoming bentonite. The success of glycerol adsorption on clays, in spite of a very low vapor pressure, suggests that more volatile polar organic molecules might effectively be studied by adsorption on clay surfaces.

¹ Contribution from Auburn Univ. Agr. Exp. Sta. and Texas Agr. Exp. Sta., College Station. This study was supported by National Aeronautics and Space Administration funds in the form of a graduate traineeship and by Water Resources Res. Instit. (Auburn Univ.) funds used for equipment. Presented before Div. S-9, Soil Sci. Soc. Amer., New Orleans, La. Nov. 13, 1968.

² Graduate Fellow, Univ. of Wisconsin and Professor of Soil Mineralogy, Dept. of Soil and Crop Sciences, Texas A&M Univ., respectively. Formerly Graduate Trainee and Associate Professor of Soil Science, Auburn Univ., Auburn, Ala.

Received for publication May 20, 1969. Accepted for publication June 3, 1970.