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Effect of Selective Dissolution on Charge and Surface Properties of an Acid Soil Clay

Published online by Cambridge University Press:  02 April 2024

Nancy Cavallaro*
Affiliation:
Department of Agronomy, Cornell University, Ithaca, New York 14853
M. B. McBride
Affiliation:
Department of Agronomy, Cornell University, Ithaca, New York 14853
*
1Present address: Centro de Edafologia, Chapingo, Mexico.
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Abstract

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To evaluate the importance of oxides to the surface chemistry of acid mineral soils, clay fractions were separated from a surface and subsurface horizon of an Inceptisol representative of many of the acid soils of the Southern Tier of New York state. Portions of the clays were treated to remove selectively noncrystalline and microcrystalline Fe and A1 oxides (acid ammonium oxalate extraction), total free iron oxides (dithionite reduction in buffered citrate solution), and organic matter (hypochlorite oxidation). Charge and ion-adsorption characteristics of the treated and untreated clays were investigated by means of Ca2+- and Cl-exchange capacities, potentiometric titrations, and electrophoretic mobility (zeta potential) measurements of the CaCl2-treated clays.

Based upon surface area and anion- and cation-exchange measurements, the Fe and A1 oxides or oxideorganic matter complexes were found to contribute a large part of the surface area and pH-dependent charge of these clays. Oxide removal increased the cation-exchange capacity (CEC) and virtually eliminated the anion-exchange capacity (AEC) at pH 3 and 5.5 while shifting the positive zeta potential (ZPC) of the B-horizon clay toward negative values. Organic matter oxidation increased the AEC at pH 3 and the CEC at pH 5.5 and markedly shifted the ZPCs of both A- and B-horizon clays toward more positive values, probably by the removal of adsorbed organics from oxide surfaces. Estimates of the ZPCs of the clays varied among the three methods used, Ca2+- and Cl-exchange capacities giving the lowest, and electrophoresis giving the highest values.

Резюме

Резюме

Фракции глин сепарировались из почвенных и подпочвенных ярусов характерных для большинства кислотных почв Южного Яруса в Штате Нью-Йорка, для оценки значения окисей в химии поверхностей почв, содержащих кислотные минералы. Порции глин обрабатывались для селективного отделения некристаллических и микрокристаллических окисей Fe и Al (экстракция при использовании щавелевокислого аммония), всех свободных окисей железа (редуцирование дитионитом в содержащем буфер растворе цитрата), и органической материи (окисление гипохлоритом). Зарядо- и ионо-адсорбционные характеристики обработанных и необработанных глин исследовались путем изменений Са2+- и Сl-обменных способностей, потенциометрического титрования и электрофорезной подвижности (потенциал зета) на глинах, обработанных СаСl2.

На основании измерений площади поверхности и анионо- и катионо-обмена, окиси Fe и Al или комплексы окисей с органической материей вносили большой вклад в величину площади поверхности и pH-зависимый заряд этих глин. Удаление окиси увеличивало катионо-обменную способность (КОС) и фактически исключало анионо-обменную способность (АОС) при pH = 3 и 5,5 в то время, как положительный потенциал зета (ПЗ) глины из яруса В перемещался в сторону отрицательных величин. Окисление органической материи увеличивало АОС при pH = 3 и КОС при pH = 5,5 и значительно перемещало величины ПЗ глин из обоих, А- и В-ярусов к более положительным значениям, вероятно, путем удаления адсорбированных органических веществ с поверхности окисей. Оценки величин ПЗ глин были различны при использовании этих трех методов; Са2+- и Сl-обменные способности давали наиболее низкие величины, а электрофорез—наибольшие величины. [E.G.]

Resümee

Resümee

Um die Bedeutung von Oxiden für die Oberbflächenchemie von sauren Mineralböden abzuschätzen, wurden die Tonfraktionen von einem Oberflächenhorizont und einem Unterbodenhorizont eines Inceptisols abgetrennt, der für viele saure Böden von Southern Tier, New York Staat, repräsentative ist. Teile der Tone wurden behandelt, um nichtkristalline und mikrokristalline Fe- and Al-Oxide (mittels saurer Ammoniumoxalat-Extraktion), die gesamten freien Eisenoxide (mittels Reduktion durch Dithionit in gepufferten Citratlösungen) und organische Substanzen (mittels Oxidation durch Hypochlorit) selektiv zu entfernen. Ladungs- und Ionenadsorptions-Charakteristika der behandelten und unbehandelten Tone wurden mittels Ca2+- und Cl-Austauschkapazitätsmessungen, potentiometrischen Titrationen und elek-trophoretischen Beweglichkeitsmessungen (Zeta-Potential) der CaCl2-behandelten Tone untersucht.

Aufgrund von Oberflächen- und Anionen- sowie Kationenaustauschmessungen zeigte sich, daß Fe- und Al-Oxide sowie Komplexe aus Oxiden und organischen Substanzen einen großen Anteil der Oberfläche und der pH-abhängigen Ladung dieser Tone ausmachen. Senn die Oxide entfernt wurden, nahm die Kationenaustauschkapazität (CEC) zu und wurde die Anionenaustauschkapazität (AEC) bei pH 3 und 5,5 praktisch zerstört, während das positive Zeta-Potential (ZPC) des B-Horizonttons gegen negative Werte verschoben wird. Die Oxidation organischer Substanzen vergrößert die AEC bei pH 3 und die CEC bei pH 5,5. Außerdem vershiebt sie die ZPCs sowohl des A- als auch des B-Horizonttons in Richtung höherer Werte, was wahrscheinlich auf dem Entfernen von adsorbierten organischen Substanzen von den Oxidoberflächen beruht. Die Schätzwerte der ZPCs der Tone variiert zwischen den drei verwendeten Methoden, wobei Ca2+- und Cl-Austauschkapazität die niedrigsten und Elektrophorese die höchsten Werte ergibt. [U.W.]

Résumé

Résumé

Pour évaluer l'importance d'oxides à la chimie de surface de sols minéraux acides, des fractions d'argile ont été separées d'un horizon de surface et sousterrain d'un représentant d'un Inceptisol d'un des nombreux sols acides de l’état de New York. On a traité des portions des argiles pour enlever sélectivement les oxides Fe et Al non-cristallins et microcristallins (extraction d'oxalate d'ammonium acide), les oxides à fer totalement libre (réduction dithionite dans une solution citrate tempérée) et la matière organique (oxidation hypochlorite). Les caractéristiques d'adsorption de charge et d'ions des argiles traités et non-traités ont été investiguées au moyen des capacités d’échange de Ca2+ et Cl, des titrations potentiomé-triques, et des mesures de mobilité électrophorétiques (potentiel zeta) des argiles traités au CaCl2.

Basé sur l'aire de surface et sur des mesures d’échange d'anions et de cations, on a trouvé que les oxides Fe et Al ou les complexes oxide-matière organique contribuaient une grande partie de l'aire de surface et de la charge dépendante du pH de ces argiles. L'enlèvement de l'oxide a augmenté la capacité d’échange de cations (CEC) et a de fait éliminé la capacité d’échange d'anions (AEC) aux pH 3 et 5,5, tandis que le potentiel zeta positif (ZPC) de l'argile de l'horizon B a été déplacé vers les valeurs négatives. L'oxidation par matière organique a augmenté l'AEC au pH 3 et la CEC au pH 5,5, et a déplacé de manière marqueé les ZPCs des argiles des horizons A et V vers des valeurs plus positives, sans doute par l'enlèvement de la matière organique adsorbée des surfaces oxides. Les estimations des ZPCs des argiles étaient variées parmi les trois méthodes utilisées, les capacités d'echange de Ca2+ et de Cl donnant les valeurs les plus basses, et l’électrophorèse donnant les plus élevées. [D. J.]

Type
Research Article
Copyright
Copyright © 1984, The Clay Minerals Society

References

Literature Cited

Bloom, P. R., 1979 Titration behavior of aluminum organic matter Soil Sci. Soc. Amer. J. 43 815817.CrossRefGoogle Scholar
Bloom, P. R., Weaver, R. M. and McBride, M. B., 1978 The spectrophotometric and fluorometric determination of aluminum with 8-hydroxyquinoline and butyl acetate extraction Soil Sci. Soc. Amer. J. 42 713716.CrossRefGoogle Scholar
Bowden, J. W., Posner, A. M. and Quirk, J. P., 1977 Ionic adsorption on variable charge mineral surfaces. Theoreticalcharge development and titration curves Aust. J. Soil Res. 15 121136.Google Scholar
Buchanan, A. S. and Oppenheim, R. C., 1972 The surface chemistry of kaolinite. III. Microelectrophoresis Aust. J. Chem. 25 18571861.CrossRefGoogle Scholar
Curtin, D. and Smillie, G. W., 1979 Origin of the pH-dependent cation exchange capacities of Irish soil clays Geoderma 22 213224.CrossRefGoogle Scholar
Follett, E. A. C., Mettardy, W. J., Mitchell, B. D. and Smith, B. F. L., 1965 Chemical dissolution techniques in the study of soil clays, parts I and II Clay Miner. 6 2343.CrossRefGoogle Scholar
Gallez, A., Juo, A. S. R. and Herbillon, A. J., 1976 Surface and charge characteristics of selected soils in the tropics Soil Sci. Soc. Amer. J. 40 601608.CrossRefGoogle Scholar
Gast, R. G., Dixon, J. B. and Weed, S. B., 1977 Surface and colloid chemistry Minerals in Soil Environments Wisconsin Soil Sci. Soc. Amer., Madison 2774.Google Scholar
Gillman, G. P. and Uehara, G., 1980 Charge characteristics of soils with variable and permanent charge minerals: II. Experimental. Soil Sci. Soc. Amer. J. 44 252254.CrossRefGoogle Scholar
Giovanni, G. and Sequi, P., 1976 Iron and aluminum as cementing substances of soil aggregates. II. Changes in stability of soil aggregates following extraction of iron and aluminum by acetylacetone in a non-polar solvent J. Soil Sci. 27 148153.CrossRefGoogle Scholar
Greenland, D. J., 1975 Charge characteristics of some ka-olinite-iron hydroxide complexes Clay Miner. 10 407416.Google Scholar
Greenland, D. J., Oades, J. M. and Sherwin, T. W., 1968 Electron microscope observations of iron oxides in some red soils J. Soil Sci. 19 123126.CrossRefGoogle Scholar
Harter, R. D., Dixon, J. B. and Weed, S. B., 1977 Reactions of minerals with organic compounds in soils Minerals in Soil Environments Wisconsin Soil Sci. Soc. Amer., Madison 709740.Google Scholar
Herrera, R. and Peech, M., 1970 Reaction of montmoril-lonite with iron (III) Soil Sci. Soc. Amer. Proc. 34 740742.CrossRefGoogle Scholar
Higashi, T., DeConick, F. and Gelande, F., 1981 Characterization of some spodic horizons of the Campine (Belgium) with dithionite-citrate, pyrophosphate and sodium hydroxide-tetraborate Geoderma 25 131142.CrossRefGoogle Scholar
Krishna Murti, G. R. S., Sarma, V. A. K. and Reggasamy, P., 1976 Amorphous ferri-aluminosilicates in some tropical ferruginous soils Clay Miner. 11 137146.CrossRefGoogle Scholar
Laverdiere, M. R. and Weaver, R. M., 1977 Charge characteristics of spodic horizons Soil Sci. Soc. Amer. J. 41 505510.CrossRefGoogle Scholar
Lorenz, R. V., 1969 Surface conductance and electrokinetic properties of kaolinite beds Clays & Clay Minerals 17 223231.CrossRefGoogle Scholar
Matejevic, E., Bell, A., Brace, R., McFadyen, P. and Alwit, R. S., 1973 Formation and surface characteristics of hydrous oxide sols Proceedings of the Symposium on Oxide-Electrolyte Interfaces Princeton, N.J. Electrochemical Soc 4564.Google Scholar
McKeague, J. M. and Day, J. H., 1966 Dithionite and oxalate-extractable Fe and Al as aids in differentiating various classes of soils Can. J. Soil Sci. 46 1322.CrossRefGoogle Scholar
McKeague, J. M., Brydon, J. E. and Miles, N. M., 1971 Differentiation of forms of extractable iron and aluminum in soils Soil Sci. Soc. Amer. Proc. 35 3338.CrossRefGoogle Scholar
Mehra, O. P., Jackson, M. L. and Swineford, A., 1960 Iron oxide removal from soils and clays by a dithionite-citrate system buffered with sodium bicarbonate Clays and Clay Minerals, Proc. 7th Natl. Conf., Washington, D.C., 1958 New York Pergamon Press 317327.Google Scholar
Moshi, A. O., Wild, A. and Greenland, D. J., 1974 Effect of organic matter on the charge and phosphate adsorption characteristics of kikuyu red clay from Kenya Geoderma 11 275283.CrossRefGoogle Scholar
Parker, J. C., Zelazny, L. W., Kamprath, S. and Harris, W. G., 1979 A critical evaluation of the extension of zero point of charge (ZPC) theory to soil systems Soil Sci. Soc. Amer. J. 43 668684.CrossRefGoogle Scholar
Pyman, M. A. F., Bowden, J. W. and Posner, A. M., 1979 The movement of titration curves in the presence of specific adsorption Aust. J. Soil Res. 17 191195.CrossRefGoogle Scholar
Rhoton, F. E., Bigham, J. M., Norton, L. D. and Smeck, N. E., 1981 Contribution of magnetite to oxalate-extractable iron in soils and sediments from the Maumee River Basin of Ohio Soil Sci. Soc. Amer. J. 45 645649.CrossRefGoogle Scholar
Schnitzer, M. and Skinner, S. I. M., 1964 Organo-metallic interactions in soils. 3. Properties of iron- and aluminum-organic matter complexes prepared in the laboratory and extracted from a soil Soil Sci. 98 197203.CrossRefGoogle Scholar
Schwertmann, U., 1973 Use of oxalate for iron extraction from soils Can. J. Soil Sci. 53 244246.CrossRefGoogle Scholar
Schwertmann, U., Taylor, R. M., Dixon, J. B. and Weed, S. B., 1977 Iron oxides Minerals in Soil Environments Wisconsin Soil Soc. Amer., Madison 145180.Google Scholar
Shuman, L. M., 1976 Zinc adsorption isotherms for soil and clays with and without iron oxides removed Soil Sci. Soc. Amer. Proc. 40 349355.CrossRefGoogle Scholar
Sposito, G., 1981 The operational definition of zero point of charge in soils Soil Sci. Soc. Amer. J. 45 292296.CrossRefGoogle Scholar
Street, N. and Buchanan, A. S., 1956 The f-potential of kaolinite particles Aust. J. Chem. 9 450466.CrossRefGoogle Scholar
Sumner, M. E., 1964 Effect of iron oxides on positive and negative charges in clays and soils Clay Miner. Bull. 5 218226.CrossRefGoogle Scholar
Swartzen-Allen, S. L. and Matijevic, E., 1975 Colloid and surface properties of clay suspensions II. Electrophoresis and cation adsorption of montmorillonite J. Coll. Interface Sci. 50 143153.CrossRefGoogle Scholar
Wada, K. and Higashi, T., 1976 The categories of aluminum- and iron-humus complexes in ando soils determined by selective dissolution J. Soil Sci. 27 357368.CrossRefGoogle Scholar
Weaver, R. M., Syers, J. K. and Jackson, M. L., 1968 Determination of silica in citrate-bicarbonate dithionite extracts of soils Soil Sci. Soc. Amer. Proc. 32 497501.CrossRefGoogle Scholar