DISTRIBUTION CONSTANT FOR EXCHANGE OF CALCIUM AND MANGANESE IN WYOMING BENTONITE

1970 ◽  
Vol 50 (1) ◽  
pp. 85-86 ◽  
Author(s):  
J. S. Clark
Keyword(s):  
Distribution Constant ◽  
Wyoming Bentonite

not available

EXCHANGE EQUILIBRIA FOR Al–BENTONITE AND MONOVALENT CATIONS

1965 ◽  
Vol 45 (2) ◽  
pp. 177-183 ◽  
Author(s):  
David Chen
Keyword(s):  
Equilibrium Distribution ◽  
Base Saturation ◽  
Monovalent Cations ◽  
Distribution Constant ◽  
Monovalent Ions ◽  
Wyoming Bentonite ◽  
Distribution Equation

Aluminum-saturated Wyoming bentonite, suspended in a solution of NH4Cl, KCl, or LiCl, was adjusted to a range of degrees of base saturation with the respective hydroxide. The distribution of the cations between solution and pH-independent exchange sites could be represented satisfactorily by an equilibrium distribution equation when the monovalent ions were NH4 or K but not when they were Li. The ion product (Al) (OH)3 was smaller at low base saturation, and increased to about 10−33.0 with NH4 and K but to only 10−33.7 with Li. The monovalent base potential (pH–pM) was a function of the magnitude of (Al) (OH)3 and the distribution constant, as well as the degree of base saturation.

THE DISTRIBUTION CONSTANT FOR EXCHANGE OF CALCIUM AND MAGNESIUM IN WYOMING BENTONITE

1966 ◽  
Vol 46 (3) ◽  
pp. 271-280 ◽  
Author(s):  
J. S. Clark
Keyword(s):  
Ionic Species ◽  
Mean Value ◽  
Neutral Salt ◽  
Distribution Constant ◽  
Ph Values ◽  
Significant Difference ◽  
Calcium And Magnesium ◽  
Excess Base ◽  
Double Hydroxides ◽  
Wyoming Bentonite

The distribution constant for exchange of calcium and magnesium ions was determined in Wyoming bentonite suspensions with pH values varying from 3.5 to 9.2. Using a neutral salt to extract the exchangeable cations, the mean value of the distribution constant using ion activities in solution was found to be 1.06 and there was no significant difference in the constant at different pH values. Thus, the presence of Al ions in the acid preparations, the precipitation of hydroxy aluminum polymers on the clay surfaces at intermediate pH values, and the precipitation of excess base in the alkaline region possibly as double hydroxides of Al and Mg or Ca had no significant effect on the exchange distribution of Mg and Ca ions.Under comparable conditions, the ion product (Al) (OH)3 had the same value in the presence of Ca or Mg. Because of this and the fact that the distribution constant for exchange was approximately 1, the two ions may be considered as a single ionic species for practical purposes in suspensions of Wyoming bentonite.

Culturability and diversity of microorganisms recovered from an eight-year old highly-compacted, saturated MX-80 Wyoming bentonite plug

2016 ◽  
Vol 126 ◽  
pp. 245-250 ◽  
Author(s):  
Daphne R. Jalique ◽  
Simcha Stroes-Gascoyne ◽  
Connie J. Hamon ◽  
Deni G. Priyanto ◽  
Clifford Kohle ◽  
...  
Keyword(s):  
Wyoming Bentonite

Diffusion of Plutonium in Compacted, Brine-Saturated Bentonite

1984 ◽  
Vol 44 ◽  
Author(s):  
E. J. Nowak
Keyword(s):  
Radioactive Waste ◽  
Packing Density ◽  
Solution Chemistry ◽  
Lithostatic Pressure ◽  
Release Rates ◽  
Rock Types ◽  
Diffusion Studies ◽  
Engineered Barriers ◽  
Radionuclide Release ◽  
Wyoming Bentonite

AbstractDiffusivities were measured for plutonium in brine-saturated compacted Wyoming bentonite. Complexities of the solution chemistry and retardation of transuranics necessitate diffusion studies under conditions that are specific for repository host rock types in this case salt. Diffusivity values in the range of 10−15 to 10−14 m2/s were obtained for bentonite at a packing density of 1800 kg/m3. That density was obtained by compaction at 15 i0Pa, a typical lithostatic pressure in a repository in salt at 650 m depth. Even a 0.05 m (2 inch) thick bentonite-containing engineered barrier could decrease radionuclide release rates by approximately 4 orders-of-magnitude if the diffusivity for that radionuclide were in the observed range of 10−15 to 10−14 m2/s. These results confirm the effectiveness of uncompacted bentonite-containing materials as engineered barriers for radioactive waste isolation.

Thermogravimetric study of the desorption of cyclohexylamine and pyridine from an acid-treated Wyoming bentonite

Clay Minerals ◽  
1991 ◽  
Vol 26 (4) ◽  
pp. 473-486 ◽  
Author(s):  
C. Breen
Keyword(s):  
Catalytic Activity ◽  
Room Temperature ◽  
Product Yield ◽  
Efficient Catalyst ◽  
X Ray ◽  
Product Yields ◽  
Thermogravimetric Study ◽  
Wyoming Bentonite

AbstractFour 15 g samples of an unsedimented Wyoming bentonite were treated with 200 cm3 of 0·025, 0·050, 0·100 and 0·250 mol dm−3 H2SO4 for 1 h at room temperature (samples I–IV, respectively). Three further 15 g samples were treated with 200 cm3 of 50% (v/v) H2SO4 for 1 h at 20°C (sample V), and 1 and 2 h under reflux (samples VI and VII, respectively). X-ray fluorescence and diffraction studies revealed that only samples VI and VII suffered any substantial structural attack. The resulting acidity of the clays, determined by cyclohexylamine desorption, indicated that sample V contained the largest number of protons at 0·59 mmol H+ (g clay)−1. Sample V was also the most efficient catalyst for the dehydration and etherification of hexan-1-ol, giving a combined product yield of 17·0% after 2 h reflux in neat reactant. The parent bentonite and samples I and II showed no discernible catalytic activity despite measured acidities of 0·1, 0·24 and 0·34 mmol H+ (g clay)−1. In contrast samples III and IV gave combined product yields of 4·5 and 11·0%, respectively, which correlated well with the measured acidities of 0·38 and 0·48 mmol H+ (g clay)−1. Samples VI and VII, prepared by reflux in acid, contained 0·3 and 0·1 mmol H+ (g clay)−1, respectively, and gave combined product yields of 13·0 and 6·0%.

Aerial surveying of Wyoming bentonite

1997 ◽  
Vol 11 (5-6) ◽  
pp. 329-335 ◽  
Author(s):  
Thomas A. Thorson
Keyword(s):  
Wyoming Bentonite

A new method for identifying Wyoming bentonite by ATR-FTIR

2006 ◽  
Vol 33 (3-4) ◽  
pp. 195-206 ◽  
Author(s):  
M KLINKENBERG ◽  
R DOHRMANN ◽  
S KAUFHOLD ◽  
H STANJEK
Keyword(s):  
New Method ◽  
Wyoming Bentonite
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