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Kaolins: Sources of Differences in Cation-Exchange Capacities and Cesium Retention

Published online by Cambridge University Press:  01 July 2024

C. H. Lim
Affiliation:
Department of Soil Science, University of Wisconsin, Madison, Wisconsin 53706
M. L. Jackson
Affiliation:
Department of Soil Science, University of Wisconsin, Madison, Wisconsin 53706
R. D. Koons
Affiliation:
Department of Soil Science, University of Wisconsin, Madison, Wisconsin 53706
P. A. Helmke
Affiliation:
Department of Soil Science, University of Wisconsin, Madison, Wisconsin 53706
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Abstract

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Seven kaolins from Georgia (southeastern U.S.A.), ranging from high to low commercial grade, were characterized by X-ray powder diffraction and chemical techniques to establish that the variation in quality was caused by impurities. The Ca and Cs cation-exchange capacities (CEC) varied from 2.67 to 8.17 and from 3.29 to 8.77 meq/100g, respectively. Selective dissolution and correlation analyses strongly indicated that expandable 2:1 minerals, particularly smectite (1.2-5.9%), were responsible for most of the observed variations in Ca CEC (r = 0.85*). The external surface CEC of kaolinite ranged from 0 to 1 meq/ 100 g. The positive significant correlation (r = 0.90**) between the Ca CEC and the K-mica content (03.9%) suggested that Ca CEC may be related to the degree of mica weathering through an expandable mineral stage.

The Cs-retention capacity (0.19–1.14 meq/100 g) was closely related to Cs-measured vermiculite content (r = 0.80*), and this content plus specific surface (R = 0.93**) or mica content (R = 0.86*). The Cs retention appeared to be primarily related to the presence of interlayer wedges at mica/vermiculite XY interfaces.

Резюме

Резюме

Семь каолинов из Джорджии (юго-восток США), представленные в диапазоне от высоко- до низкокачественных коммерческих марок, были охарактеризованы порошковым методом рентгеноструктурного анализа и химическими анализами, чтобы доказать что изменения качества вызываются примесями. Катионно-обменные способности (КОС) Са и Cs изменялись от 2,67 до 8,17 и от 3,29 до 8,77 М.ЭК./100 г соответственно.Селективные анализы растворения и корреляции убедительно доказали, что расширяющиеся минералы 2:1, особенно смектит (1,22–5,9%), обусловили большинство замеченных изменений КОС Са (г = 0,85*). Наружная поверхностная КОС каолинита колеблется от 0 до 1 М.ЭК./ЮО г. Существенная положительная корреляция (г = 0,90**) между КОС Са и содержанием К-слюды (02–3,9%) указывает на то, что КОС Са может быть связана со степенью выветривания слюды в течение фазы расширения минерала.

Способность удержания Cs (0,19–1,14 М.ЭК./ЮО г) тесно связана с измеренным по Cs содержанием вермикулита (г = 0,80*) и этим содержанием плюс удельной поверхностью (R = 0,93**) или содержанием слюды (R = 0,86*). Удержание Cs, по-видимому, связано в основном с присутствием межслойных клиньев в промежутках XY слюда/вермикулит. [N.R.]

Resümee

Resümee

Sieben Kaoline aus Georgia (südöstliche USA), die von hoch- bis niedrig-qualitativ reichen, wurden mittels Röntgenpulverdiffraktometrie und chemischen Methoden charakterisiert, um festzustellen, daß die Qualitätsunterschiede durch Verunreinigungen hervorgerufen werden. Die Ca- und Cs-Kationenaustauschkapazitäten, (CEC), variierten von 2,67 bis 8,17 bzw. von 3,29 bis 8,77 mÄq/100 g. Selektive Auflösungs- und Korrelationsanalysen zeigen sehr stark an, daß quellfähige 2:1 Minerale, vor allem Smektit (1,2–5,9%), für die meisten der beobachteten Variationen in der Ca CEC (r = 0,85*) verantwortlich sind. Die CEC der äußeren Oberfläche von Kaolinit reicht von 0–1 mÅq/100 g. Die positive beachtliche Korrelation (r = 0,90**) zwischen der Ca CEC und dem Gehalt an K-Glimmer (0–3,9%) deutet daraufhin, daß die Ca CEC im Zusammenhang stehen könnte mit dem Ausmaß, in dem die Glimmerverwitterung durch ein Stadium eines quellfähigen Minerales geht.

Die Cs-Retentionskapazität (0,19–0,14 mÄq/100 g) stand in engem Zusammenhang mit dem Cs-gemessenen Vermiculitgehalt (r = 0,80*) und mit diesem Gehalt plus spezifischer Oberfläche (R = 0,93**) bzw. Glimmergehalt (R = 0,86*). Die Cs-Retention scheint vor allem mit der Anwesenheit von Zwischenschichtkeilen an den Glimmer/Vermikulit XY Grenzflächen im Zusammenhang zu stehen. [U.W.]

Résumé

Résumé

Sept kaolins de Géorgie (Sud Est des E.U.) s’étageant de grade commercial haut à bas ont été caractérisés par diffraction poudrée aux rayons-X et par des techniques chimiques pour établir que la variation en quantité était causée par des impuretés. Les capacités d’échange de cations Ca et Cs (CEC) ont varié de 2,67 à 8,17 et de 3,29 à 8,77 meq/100 g, respectivement. Les analyses de dissolution sélective et de corrélation ont intensément indiqué que les minéraux expansibles 2:1, la smectite en particulier, (1,25,9%), étaient responsables pour la plupart des variations observées dans Ca CEC (r = 0,85*). La surface externe CEC de la kaolinite s’étageait de 0 a 1 meq/100 g. La corrélation positive significative (r = 0,90**) entre Ca CEC et le contenu en mica-K (0–3,9%) suggère que Ca CEC peut être apparenté au degré d'altération du mica à travers un stage minéral expansible. La capacité de retention-Cs (0,19–1,14 meq/100 g) était apparentée de près au contenu en vermiculite mesuré Cs (r = 0,80*), et ce contenu plus la surface spécifique (R = 0,93**) ou le contenu en mica (R = 0,86*). La rétention de Cs semblait ètre principalement apparentée à la présence de parties interfeuillets aux interfaces mica/vermiculite XY. [D.J.]

Type
Research Article
Copyright
Copyright © Clay Minerals Society 1980

References

Abdel-Kader, F. H. Jackson, M. L. and Lee, G. B., (1978) Soil kaolinite, Vermiculite, and chlorite identification by an improved lithium DMSO X-ray diffraction test Soil Sci. Soc. Amer. J. 42 163167.CrossRefGoogle Scholar
Alexiades, C. A. and Jackson, M. L., (1966) Quantitative clay mineralogical analysis of soils and sediments Clays & Clay Minerals 14 3552.CrossRefGoogle Scholar
Barshad, I., (1954) Cation exchange in micaceous minerals: I. Replaceability of ammonium and potassium from Vermiculite, biotite, and montmorillonite Soil Sci. 78 5776.CrossRefGoogle Scholar
Bolland, M. D. A. Posner, A. M. and Quirk, J. P., (1976) Surface change on kaolinites in aqueous suspension Aust. J. Soil Res. 14 197216.Google Scholar
Bundy, W. M. Johns, W. D. and Murray, H. H., (1966) Interrelationships of physical and chemical properties of kaolinites Clays & Clay Minerals 14 331345.CrossRefGoogle Scholar
Coleman, N. T. Lewis, R. J. and Craig, D., (1963) Sorption of cesium by soils and its displacement by salt solutions Soil Sci. Soc. Amer. Proc. 27 290294.CrossRefGoogle Scholar
Dolcater, D. L. Lotse, E. G. Syers, J. K. and Jackson, M. L., (1968) Cation exchange selectivity of some clay-sized minerals and soil materials Soil Sci. Soc. Amer. Proc. 32 795798.CrossRefGoogle Scholar
Ferris, A. P. and Jepson, W. B., (1975) The exchange capacities of kaolinite and the preparation of homoionic clays J. Colloid Interface Sci. 51 245259.CrossRefGoogle Scholar
Francis, C. W. and Brinkley, F. S., (1976) Preferential adsorption of Cs137 to micaceous minerals in contaminated fresh water sediment Nature 260 511513.CrossRefGoogle Scholar
Hinckley, D. N. and Bates, T. F., (1960) Evaluation of the amount and distribution of montmorillonite in some Georgia and South Carolina kaolins Clays & Clay Minerals 8 1821.CrossRefGoogle Scholar
Jackson, M. L., (1963) Interlayering of expansible layer silicates in soils by chemical weathering Clays & Clay Minerals 11 2946.Google Scholar
Jackson, M. L., (1975) Soil Chemical Analysis3-Advanced Course 2nd ed. Madison, Wisconsin 10th printing, published by the author.Google Scholar
Jackson, M. L. and Abdel-Kader, F. H., (1978) Kaolinite intercalation procedure for all sizes and types with X-ray diffraction spacing distinctive from other phyllosilicates Clays & Clay Minerals 26 8187.CrossRefGoogle Scholar
Johns, W. D. and Murray, H. H., (1959) Empirical crystallinity index for kaolinite Prog. Abstr. Geol. Soc. Amer. 70 1624.Google Scholar
Keller, W. D. and Haenni, R. P., (1978) Effects of micro-sized mixtures of kaolin minerals on properties of kaolinites Clays & Clay Minerals 26 384396.CrossRefGoogle Scholar
Komameni, S., (1978) Cesium sorption and desorption behavior of kaolinites Soil Sci. Soc. Amer. J. 42 531532.CrossRefGoogle Scholar
Lee, S. Y. Jackson, M. L. and Brown, J. L., (1975) Micaceous occlusions in kaolinite observed by ultramicrotomy and high resolution electron microscopy Clays & Clay Minerals 23 125129.CrossRefGoogle Scholar
Lyons, S. C., (1958) Clays Tappi Monograph 20 57115.Google Scholar
Milford, M. H. and Jackson, M. L., (1962) Specific surface determination of expansible layer silicates Science 135 929930.CrossRefGoogle ScholarPubMed
Murray, H. H. and Lyons, S. C., (1960) Further correlation of kaolinite crystallinity with chemical and physical properties Clays & Clay Minerals 8 1117.CrossRefGoogle Scholar
Ormsby, W. C. Shartsis, J. M. and Woodside, K. H., (1962) Exchange behavior of kaolins of varying degrees of crystallinity J. Amer. Ceram. Soc. 45 361366.CrossRefGoogle Scholar
Range, K. J. Range, A. and Weiss, A., (1969) Fire-clay type kaolinite or fire-clay mineral? Experimental classification of kaolinite-halloysite minerals Proc. 3rd Int. Clay Conf. 1 313.Google Scholar
Sawhney, B. L., (1964) Sorption and fixation of microquantities of Cs by clay minerals: effect of saturating cations Soil Sci. Soc. Amer. Proc. 28 183186.CrossRefGoogle Scholar
Schulz, R. K. Overstreet, R. and Barshad, I., (1960) On the soil chemistry of cesium-137 Soil Sci. 89 1627.CrossRefGoogle Scholar
Van Olphen, H., (1966) Collapse of potassium montmorillonite clays upon heating—“potassium fixation” Clays & Clay Minerals 14 117132.CrossRefGoogle Scholar