Sodium-calcium ion exchange on clay minerals at moderate to high ionic strengths. [Dissertation]

Technical Report · Sat Dec 01 04:00:00 EST 1979

DOI:https://doi.org/10.2172/5490921· OSTI ID:5490921

Rogers, W. J.

Sodium-calcium ion exchange on several clay minerals was studied at ionic strengths ranging from 0.01 to above 1.0. The minerals studied included attapulgite, illite, kaolin, and several montmorillonites. Distribution coefficients of calcium and sodium were obtained for the minerals over a wide range of solution conditions at pH five and equilibrium constants were calculated. The distribution coefficient of calcium, D/sub Ca/, was studied as a function of time, solution pH, loading, sodium concentration, and ionic strength fraction of sodium in constant ionic strength solutions. The distribution coefficient of sodium, D/sub Na/, was also studied as a function of time, loading, and sodium ionic strength fraction in constant total ionic strength solutions. Values of equilibrium constants calculated from distribution coefficients for solutions of constant ionic strength scattered bwteen 2 and 10 kg/kg for the montmorillonites and attapulgite while equilibrium constants for illite ranged from 5 to 10 kg/kg. No equilibrium constants for kaolin were calculated since distribution coefficients of sodium on this clay were too small to be measured. It was found that equilibrium constants at trace sodium loading were generally lower than those for higher sodium loadings by an order of magnitude or more due to the sensitivity of sodium distribution coefficients to the concentration of sodium in the clay at low loadings. Theoretical and experimental treatments of ion exclusion were included.

• Research Organization: Tennessee Univ., Knoxville (USA)
• DOE Contract Number: EY-76-C-05-0033
• OSTI ID: 5490921
• Report Number(s): DOE/TIC-10284
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400105* -- Separation Procedures
510100 -- Environment
Terrestrial-- Basic Studies-- (-1989)
54 ENVIRONMENTAL SCIENCES
ALKALI METALS
ALKALINE EARTH METALS
ATTAPULGITE
CALCIUM
CHEMISTRY
CLAYS
DATA
DATA FORMS
DISTRIBUTION FUNCTIONS
ELEMENTS
ENVIRONMENTAL TRANSPORT
EQUILIBRIUM
EXPERIMENTAL DATA
ILLITE
INFORMATION
INORGANIC ION EXCHANGERS
ION EXCHANGE
ION EXCHANGE MATERIALS
KAOLIN
MASS TRANSFER
METALS
MINERALS
MONTMORILLONITE
NUMERICAL DATA
RADIONUCLIDE MIGRATION
SODIUM
SOIL CHEMISTRY
SORPTIVE PROPERTIES
SURFACE PROPERTIES
TABLES