Thesis for the Degree of Doctor of Philosophy - DTU Orbit

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9). The results shows that iodine present in solution was nearly quantitatively removed (around 2.5-7.6 % of the total iodine remains in the water phase after batch experiment, Table 9, experiment numbers 3 and 4) even when the concentration of natural organic iodine compounds extracted from soils and seaweed were added to the fresh water (Table 9) increase significantly. By contrast when using a mixture of K2S2O8/NaClO as an oxidant, relatively high (30 - 40%) amount of iodine remains in the water phase after the batch experiment (Table 10, experiments numbers 9 and 10). Due to the low amount of iodine that remains in the water phase after the batch experiments (Table 9, experiments numbers 3-6) we conclude that the oxidation of iodine organic matter by using K2S2O8 followed by reduction of iodine species and precipitation with silver nitrate can be a potential method for determination of total iodine in freshwater samples. Because more samples can be treated simultaneously, the method is rapid and very suitable for field use if needed. Table 9 Main protocols for oxidation of iodine organic matter in water samples by using K2S2O8 for quantification of total iodine. The volume of water was 200ml in all experiments. The experiments were conducted at room temperature. All forms of iodine resulted after destruction of organic iodine were converted to iodide by adding 1mL of 1M K2S2O5 at pH 1-2 with 3M HNO3 and finally precipitated as silver iodide by adding 1-2 mL of 1M AgNO3. After 30’ stirring and centrifugation at 3000 x g for 30’ the silver iodide precipitate is separated from water. Experiment number Experiment setting 127 I concentration in studied sample (ppb) The fraction of 127 I that remains in the water phase after batch experiment (%) 1 0.2 g K2S2O8/2 mL of iodine NOM extracted from seaweed with water/sample pH 6-7/2h stirring 107.2 9.8 2 0.2 g K2S2O8/4 mL of iodine HSs extracted from soil with 5% TMAH/sample pH 10-11/2h stirring 43.6 19.4 3 0.5 g K2S2O8/3 mL of iodine NOM extracted from seaweed with water/sample pH 6-7/2h stirring 100.9 2.5 4 0.5 g K2S2O8/3 mL of iodine HSs extracted from soil with 5% TMAH/sample pH 10-11/2h stirring 47.1 7.6 5 1 g K2S2O8/4 mL mL of iodine NOM extracted from seaweed with water/sample pH 6-7/2h stirring 145.1 5.1 6 1 g K2S2O8/4 mL of iodine HSs extracted from soil with 5% TMAH/sample pH 10-11/2h stirring 49.80 10.0 7 0.5 g K2S2O8/2 mL of iodine NOM extracted from seaweed with water/sample pH 6-7/17h stirring 71.4 13.8 8 1 g K2S2O8/2 mL of iodine NOM extracted from seaweed with water/sample pH 6-7/17h stirring 72.0 11.9 NOM – natural organic matter; HSs – humic substances; TMAH - tetramethylammonium hydroxide; However, direct precipitation of total iodine (without oxidation of iodine organic matter) from freshwater as silver iodine was also performed (Table 10, experiments numbers 11-14). As a result, the relative amount of total iodine was determined to be 8-15% in the filtrate after the batch experiment (Table 10, experiments 42
numbers 11-14), which is about the same as the experiments above using 0.01M K2S2O8 (Table 9). These findings might be attributed to the sample matrix (organic matter), which may partially precipitate when adding silver nitrate, and thus the iodide, iodate and organic iodine were precipitated together. As long as large molecular weight humic molecules are the main carrier of organic iodine species direct co- precipitation without previous oxidation of the sample may thus be an alternative method. In fresh water highly enriched in organic matter (e.g. Humic substances) the increased ion strength due to the addition of the chemicals used induce a visible coagulation and co-precipitation of organic matter. Table 10 Main protocols for oxidation of iodine organic matter in water samples for quantification of total iodine.The volume of water was 200ml in all experiments. The experiments were conducted at room temperature. Experiment number 9 K2S2O8 and NaClO 10 K2S2O8 and NaClO Oxidant Experiment setting 0.5 g K2S2O8/5 mL of 15% NaClO/3 mL of iodine NOM extracted from seaweed with water/2h stirring /1mL of 1M K2S2O5/pH 1-2 with HNO3/1-2 mL of 1M AgNO3/30’ stirring/ 30’centrifugation at 3000 x g 0.5 g K2S2O8/5 mL of 15% NaClO/3 mL iodine HSs extracted from soil with 5% TMAH/sample/2h stirring /1mL of 1M K2S2O5/pH 1-2 with HNO3/1-2 mL of 1M AgNO3/30’ stirring/30’centrifugation at 3000 x g 11 None 2 mL of iodine NOM extracted from seaweed with water/ pH 1-2 with HNO3/1-2 mL of 1M AgNO3/30’stirring/30’centrifugation at 3000 x g 12 None 2 mL of iodine HSs extracted from soil with 5% TMAH / pH 1-2 with HNO3/1-2 mL of 1M AgNO3/30’stirring/30’centrifugation at 3000 x g 13 None 2 mL of iodine NOM extracted from seaweed with water/ 1mL of 1M K2S2O5 / pH 1-2 with HNO3/1-2 mL of 1M AgNO3/30’stirring/30’centrifugation at 3000 x g 127 I concentration in original sample (ppb) The fraction of 127 I that remains in the water phase after batch experiment (%) 105.9 39.7 49.1 29.1 254.3 8.7 229.3 8.4 212.2 8.7 14 None 2 mL of iodine HSs extracted from soil with 5% TMAH/ 1-2 mL of 1M AgNO3/ 30’stirring /30’centrifugation at 3000 x g 211 15 NOM – natural organic matter; HSs – humic substances; TMAH - tetramethylammonium hydroxide 43
Page 1 and 2: Chemical Speciation Analysis and En
Page 3 and 4: Thesis for the Degree of Doctor of
Page 5 and 6: Abstract This thesis deals with che
Page 7 and 8: environment since they reflect the
Page 9 and 10: organiske jodformer. Adsorption af
Page 11 and 12: None of this would have been possib
Page 13 and 14: Abbreviations and acronyms b+ - pos
Page 15 and 16: 3.1 Analytical Development………
Page 17 and 18: Table 1 Some properties of iodine P
Page 19 and 20: In soils/sediments iodine occurs as
Page 21 and 22: Table 2 Nuclear properties of iodin
Page 23 and 24: Liquid scintillation counting (LSC)
Page 25 and 26: The bioavailability of radioactive
Page 27 and 28: data (Englund et al., 2010; Hou et
Page 29 and 30: 2. Analytical procedures used in th
Page 31 and 32: 2.3 Quantification of total iodine
Page 33 and 34: Fig. 5 Quantification of total iodi
Page 35 and 36: iodate were measured by counting 12
Page 37 and 38: Fig. 6 Sequential extraction proced
Page 39 and 40: a Fig. 8 Calibration curve for (a)
Page 41 and 42: experiment was subjected to combust
Page 43: Table 7 Adsorption of iodine specie
Page 47 and 48: marine environment from nuclear fue
Page 49 and 50: 127 I - (ppb) 127 IO3 - (ppb) a b 1
Page 51 and 52: Although the oxygen concentration d
Page 53 and 54: 129 I TBq 2,00E+00 1,80E+00 1,60E+0
Page 55 and 56: • Adsorption of iodine species on
Page 57 and 58: Reference Aldahan A, Kekli A, Possn
Page 59 and 60: Fuge R& Johnson C. 1986. The geoche
Page 61 and 62: Lo´pez-Gutie´rrez JM, Garcı ´a-
Page 63 and 64: Shinohara K. 2004. Measurement and
Page 65 and 66: http://www.irsn.fr/EN/news/Document
Page 67 and 68: Review Analytica Chimica Acta 632 (
Page 69 and 70: Table 1 Nuclear properties and prod
Page 71 and 72: Fig. 2. Liquid discharges of 129 I
Page 73 and 74: Fig. 5. Schematic diagram and pictu
Page 75 and 76: 129 I in iodide and iodate is then
Page 77 and 78: Fig. 8. Diagram of air sampler for
Page 79 and 80: Fig. 10. Iodine L3-edge (a) and K-e
Page 81 and 82: analysis of 129 I in water sample a
Page 83 and 84: Yi P, Aldahan A, Hansen V, Possnert
Page 85 and 86: FIGURE 1. Sampling sites (the red s
Page 87 and 88: FIGURE 3. Horizontal distribution o
Page 89 and 90: FIGURE 5. Time series data of 129 I
Page 91 and 92: Environmental Science & Technology
Page 93 and 94: prepared using KI and KIO3. No diff
Page 95 and 96:
of their contribution to the Baltic
Page 97 and 98:
Fig. S-1 Sampling sites (the red so
Page 99 and 100:
Fig. S-3 Vertical distribution of I
Page 101 and 102:
Fig. S-5 Marine discharges function
Page 103 and 104:
Fig.S-7 Relationship between I-129
Page 105 and 106:
Table S-1 Results of I-129 and I-12
Page 107 and 108:
S17
Page 109 and 110:
Paper III Hansen,V., Yi, P., Hou, X
Page 111 and 112:
conversion process between iodide a
Page 113 and 114:
Table 1 Analytical results of 129 I
Page 115 and 116:
August April I-129 iodide ( 10 8 at
Page 117 and 118:
References Aldahan A, Kekli A, Poss
Page 119 and 120:
Partition of iodine ( 129 I and 127
Page 121 and 122:
Norway (Table 1). CTD-casts with ox
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5. Discussion 5.1. Separation of hu
Page 125 and 126:
In the present study 40e60% of 129
Page 127 and 128:
Hutta, M., Gora, R., 2003. Novel st
Page 129 and 130:
Analysis of 129 I and 127 I in arch
Page 131 and 132:
et al., 2002). Due to the fact that
Page 133 and 134:
espectively. The iodine was leached
Page 135 and 136:
salinities in the same area. Apart
Page 137 and 138:
North Sea. 129 I/ 127 I ratios in w
Page 139 and 140:
Table 2 Analytical results of 129-I
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129 I/ 127 I 1,40E-07 1,20E-07 1,00
Page 143 and 144:
References Aldahan A, Englund E, Po
Page 145 and 146:
O’Dowd, C.; Jimenez, J. L.; Bahre
Page 147 and 148:
Iodine ( 129 I and 127 I) speciatio
Page 149 and 150:
water in winter by molecular oxygen
Page 151 and 152:
0.2 M KNO3. The effluent and the wa
Page 153 and 154:
maximum values is at 0.03-0.06×10
Page 155 and 156:
into the English Channel from the L
Page 157 and 158:
References Aldahan A, Kekli A, Poss
Page 160 and 161:
Risø-PhD-81(EN)
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Thesis for the Degree of Doctor of Philosophy - DTU Orbit

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