UNDERSTANDING VARIATION IN PARTITION COEFFICIENT, Kd ...

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The soil-only data set was frequently incomplete with regard to supporting data describing the experimental conditions under which the cesium K d values were measured (Table D.2). Quite often the properties of the solid phase or the dissolved cesium concentration used in the K d experiments were not reported. For instance, there were only 3 cesium K d values that had accompanying clay content data, 11 cesium K d values that had accompanying cation exchange data, and 11 cesium K d values that had accompanying surface area data (Table D.2). Consequently, it was not possible to evaluate adequately the relationship between cesium K d values and these important, independent soil parameters. This is discussed in greater detail below. D.2.0 Approach and Regression Models D.2.1 Correlations with Cesium K d Values A matrix of the correlation coefficients for the parameters included in the data set containing K d values determined in experiments with both soils and pure mineral phases is presented in Table D.3. The correlation coefficients that are significant at or less than the 5 percent level of probability (P # 0.05) are identified with a footnote. The parameter with the largest correlation coefficient with cesium K d was CEC (r = 0.52). Also significant was the correlation coefficient between cesium K d values and surface area (r = 0.42) and CEC and clay content (r = 0.64). The poor correlation between cesium aqueous concentration ([Cs] aq) and cesium K d values can be attributed to the fact that the former parameter included concentration of the solution prior and after contact with the soils. We report both under the same heading, because the authors frequently neglected to indicate which they were reporting. More frequently, the spike concentration (the cesium concentration prior to contact with the soil) was reported, and this parameter by definition is not correlated to K d values as well as the concentrations after contact with soil (the denominator of the K d term). A matrix of the correlation coefficients for the parameters included in the data set containing K d values determined in experiments with only soils is presented in Table D.4. As mentioned above (Table D.2), the reports in which soil was used for the K d measurements tended to have little supporting data about the aqueous and solid phases. Consequently, there was little information for which to base correlations. This occasionally resulted in correlations that were not scientifically meaningful. For example, the correlation between CEC and cesium K d was -0.83, for only 11 observations (10 degrees of freedom). The negative sign of this correlation contradicts commonly accepted principles of surface chemistry. D.5
Table D.3. Correlation coefficients (r) of the cesium K d value data set that included soils and pure mineral phases. [Data set is presented in Section D.3.] Cesium K d Cesium K d 1.00 Clay Content Clay Content 0.05 1.00 Mica 0.29 0.00 1.00 pH 0.10 -0.11 0.08 1.00 Mica pH CEC Surface Area CEC 0.52 a 0.64 a NA 0.37 1.00 Surface Area 0.42 a [Cs] aq -0.07 0.85 a 0.35 NA -0.11 0.47 a D.6 1.00 0.29 0.13 -0.17 -0.15 a Correlation coefficient is significant at the 5% level of significance (P # 0.05). Table D.4. Correlation coefficients (r) of the soil-only data set. [Data set is presented in Section D.4.] Cesium K d Cesium K d 1.00 Clay Content Clay Content -0.21 1.00 Mica 0.27 0 1.00 pH 0.11 0.4 0.07 1.00 CEC -0.83 NA 0.99 1 Surface Area -0.31 NA 0.99 1 Mica pH CEC Surface Area 0.05 1.00 -0.03 0.37 1.00 [Cs] aq 0.18 NA 0.09 -0.04 0.00 0 1 Correlation coefficient is significant at >5% level of significance (P # 0.05).
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United States Office of Air and Rad
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NOTICE The following two-volume rep
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This publication is the result of a
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TO COMMENT ON THIS GUIDE OR PROVIDE
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CONTENTS NOTICE ...................
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Concentrations Extractable Iron Con
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Appendix A - Acronyms and Abbreviat
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Figure E.1. Variation of K d for Cr
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Table 5.16. Uranium(VI) aqueous spe
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Table H.3. Simple and multiple regr
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1.0 Introduction The objective of t
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discussed. The geochemical modeling
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2.0 The K d Model The simplest and
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track many more parameters and some
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of interest. The retardation factor
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(e.g., soil). An increasing body of
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complexation constants for the cont
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the soil column. Additionally, the
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Element Table 5.2. Concentrations o
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5.2.3 Aqueous Speciation Cadmium fo
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5.2.4 Dissolution/Precipitation/Cop
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cadmium, indicating that cadmium an
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5.2.6.2.2 Limits of K d Values with
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organic chelates (e.g., EDTA). Init
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(tarapacaite) in chromium sludge fr
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K d). Soils containing Mn oxides ox
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Table 5.7. Estimated range of Kd va
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most common valence state of lead e
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Table 5.8. Lead aqueous species inc
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Under reducing conditions, galena (
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C Adsorption of lead increases with
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(Choppin, 1983). Plutonium hydrolyt
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Table 5.10. Plutonium aqueous speci
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5.6.5 Sorption/Desorption Plutonium
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content in the system. Additionally
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much greater concentrations. Thus,
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exchanged which they attributed to
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up tables was based in part on thei
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organic complexes likely predominat
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Thorium undergoes hydrolysis in aqu
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The distribution of thorium aqueous
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from about 10 -8.5 mol/l (0.0007 mg
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Based on the assumptions and limita
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5.10 Tritium Geochemistry And K d V
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uranium. Uranium(VI) species domina
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gives 0.1 to 10 µg/l as the range
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mineral in reducing ore zones (Fron
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Percent Distribution 100 80 60 40 2
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5.11.6 Partition Coefficient, K d ,
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No attempt was made to statisticall
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Table 5.18. Selected chemical and t
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Another objective of this report is
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6.0 REFERENCES Adriano, D. C. 1992.
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Bensen, D. W. 1960. Review of Soil
Page 119 and 120: Metals by Geomedia. Variables, Mech
Page 121 and 122: EPA (U.S. Environmental Protection
Page 123 and 124: Griffin, R. A., A. K. Au, and R. R.
Page 125 and 126: + Keeney-Kennicutt, W. L., and J. W
Page 127 and 128: Mattigod, S. V., A. L. Page, and I.
Page 129 and 130: Oscarson, D. W., and H. B. Hume. 19
Page 131 and 132: Relyea, J. F. and D. A. Brown. 1978
Page 133 and 134: Schultz, R. K., R. Overstreet, and
Page 135 and 136: Szalay, A. 1964. “Cation Exchange
Page 137 and 138: Yariv, S., and H. Cross. 1979. Geoc
Page 139 and 140: APPENDIX A Acronyms, Abbreviations,
Page 141 and 142: PC Personal computers operating und
Page 143 and 144: A.3.0 List of Symbols and Notation
Page 145 and 146: APPENDIX B Definitions
Page 147 and 148: Clay Content - particle size fracti
Page 149 and 150: Polynuclear Species - an aqueous sp
Page 151 and 152: C.1.0 Background Appendix C Partiti
Page 153 and 154: Cadmium K d Table C.2. Correlation
Page 155 and 156: C.3.0 Data Set for Soils Table C.4
Page 157 and 158: Cd K d (ml/g) Clay Cont. (wt%) pH C
Page 167 and 168: D.1.0 Background Appendix D Partiti
Page 169: A second data set (see Section D.4)
Page 173 and 174: By transposing the CEC and cesium K
Page 175 and 176: Table D.6. Cesium K d values measur
Page 177 and 178: eported in Table D.8 are described
Page 179 and 180: a 1 b 1 Range of Solution Cs Concen
Page 181 and 182: Figure D.4. Generalized cesium Freu
Page 183 and 184: Table D.10. Estimated range of K d
Page 185 and 186: D.3.0 K d Data Set for Soils and Pu
Page 187 and 188: Cesium Kd (ml/g) Clay (wt.% ) Mica
Page 193 and 194: Cesium K d (ml/g) Clay (wt%) Mica (
Page 195 and 196: Bruggenwert, M. G. M., and A. Kamph
Page 197 and 198: Shiao, S. Y., P. Rafferty, R. E. Me
Page 199 and 200: E.1.0 Background Appendix E Partiti
Page 201 and 202: chromium-reductive soils may stem f
Page 204 and 205: E.2.0 Approach The approach used to
Page 206 and 207: Table E.3. Estimated range of K d v
Page 208 and 209: Table E.4. Data from Rai et al. (19
Page 210 and 211: E.4.0 References Davis, J. A. and J
Page 212 and 213: APPENDIX F Partition Coefficients F
Page 214 and 215: (CEC) of the soils. Such an anomaly
Page 216 and 217: Table F.1. Summary of K d values fo
Page 218 and 219: Figure F.2. Variation of K d as a f
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F.4.0 References Abd-Elfattah, A.,
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APPENDIX G Partition Coefficients F
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A number of investigators have exam
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pH value, which is typical of the m
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These significant reductions in ads
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This is typically accomplished by t
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The scatterplots are typically disp
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Table G.2. Regression models for pl
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G.4.0 References Barney, G. S. 1984
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Nelson, D. M., R. P. Larson, and W.
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APPENDIX H Partition Coefficients F
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1.6 ml/g for a measurement made on
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Figure H.1. Relation between stront
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Figure H.2. Relation between stront
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H.2.4 Approach Figure H.4. Relation
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A second look-up table (Table H.5)
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Sr K d (ml/g) Clay Content (%) pH C
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Sr K d (ml/g) Clay Content (%) pH C
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Sr K d (ml/g) Clay Conten t (%) pH
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Konishi, M., K. Yamamoto, T. Yanagi
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APPENDIX I Partition Coefficients F
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descriptive statistics of the thori
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Figure I.1. Linear regression betwe
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The look-up table (Table I.5) for t
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Thorium K d (ml/g) pH Clay (wt.%) C
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Rai, D., A. R. Felmy, D. A. Moore,
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J.1.0 Background Appendix J Partiti
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J.2.2 Uranium K d Studies on Soils
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Washington. The studies included an
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and then decreases with increasing
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Kd (ml/g) 100,000 10,000 1,000 100
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papers. Warnecke et al. (1984) indi
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Anderson et al. (1982) summarize an
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McKinley and Scholtis (1993) compar
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In a similar comparison of sorption
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J.3.1 K d Values as a Function ff p
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discussed, and one would have to ma
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al., 1992; and others). These refer
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· Manskaya et al. (1956) studied a
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concentrations of humic acid, there
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pH U Kd (ml/g) Clay Cont. (wt.%) CE
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J.6.0 References Ames, L. L., J. E.
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Erikson, R. L., C. J. Hostetler, R.
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R. C. Ewing. Materials Research Soc
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Sheppard, M. I., and D. H. Thibault
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Yamamoto, T., E. Yunoki, M. Yamakaw
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