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 Brown, J. M. Articles by Bartholomew, W. V. Search for Related Content PubMed Articles by Brown, J. M. Articles by Bartholomew, W. V. Agricola Articles by Brown, J. M. Articles by Bartholomew, W. V.

Sorption of Gaseous Ammonia by Clay Minerals as Influenced by Sorbed Aqueous Vapor and Exchangeable Cations¹

ABSTRACT

Ammonia sorption by homoionic clay systems containing small amounts of adsorbed aqueous vapor was investigated by manometric techniques employing equilibrium measurements in a special sorption apparatus.

Sorption isotherms from this investigation indicated that there is considerable interaction between ammonia sorption and moisture levels of the clays. At ammonia pressures below 60 to 100 mm. Hg, "dry" bentonite and halloysite sorbed more ammonia than comparable moist clays. At higher ammonia pressures, moist clays sorbed more ammonia than "dry" clays with the greatest amount of sorption occurring at the higher moisture levels.

There was evidence of competition between aqueous vapor and ammonia for sorption sites on the clays. The kind of cation on the exchange complex also exerted an influence on ammonia sorption by moist clay, the mechanism of influence probably arising in part through alteration of the quantity and nature of the water of hydration.

The same order of influence of exchangeable cations on ammonia sorption occurred with the moist clays as was previously reported for dry clays, i.e., Al-clay > Ca-clay > K-clay.

¹ Contribution from the Soils Department, North Carolina Agr. Exp. Sta., North Carolina State College, Raleigh. Published with the approval of the Director as Paper No. 1440 of the Journal Series. Presented before Div. III, Soil Science Society of America, at Chicago, Ill., Dec. 5, 1960.

² Formerly Agronomy Extension Specialist (Soil Management), North Carolina State College, now Agronomist, National Cotton Council of America, and Professor of Soils, North Carolina State College, respectively.

Received for publication April 23, 1962. Accepted for publication July 19, 1962.