Thesis for the Degree of Doctor of Philosophy - DTU Orbit

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Table 5 HPLC-ICPMS results of iodine species in natural water samples collected in Denmark. Sample Location Sampling date pH Total iodine (nM) I- (nM) IO3- (nM) Other iodine species (nM) Seawater Færøerne Havvand 11-12-2008 6.5 411.1 103.78 253.54 53.78 Rain water Ejby 03-02-2009 5 6.55 0.78 0.4 5.37 Lake Hostrup Sø 26-01-2009 5.5 47.2 0.99 0.88 45.32 River Suså 03-02-2009 7 74.5 1.16 4.05 70.45 Groundwater EJ BY 27-01-2009 7 42.71 1.55 15.44 27.27 Due to the low concentrations of 129 I in the environment ( 129 I/ 127 I is about10 -12 , Fehn et al., 2007; Hou et al., 2009), the above developed method cannot be applied for speciation analysis of anthropogenic iodine in environmental samples but can be applied for highly contaminated 129 I water samples. 3.1.2 Quantification of total iodine-129 in freshwater and seawater samples by adsorption on activated charcoal or DEAE 32 cellulose (unpublished results). Adsorption of iodine species onto activated charcoal was previously applied Woittiez et al.(1991). Several studies have been conducted in order to remove aquatic organic compound by adsorption onto activated carbon and anion exchange resin (Chen et al., 1996; Chen 1999). Activated carbon is most often involved in the purification of water. DEAE 32 cellulose, an anion exchange resin (charge independent of pH), has also been proven very useful in isolating humic material from fresh waters (Hiraide et al, 1994). The results of the present study show that iodine from the studied lake water (with a total concentration of iodine-127 of 20 ppb) can be easily adsorbed onto 5g activated charcoal washed with double distilled water or ethanol after stirring for 2h (Table 6, experiments number 5-8 and 13-15). The sorption of iodine was not affected by the pH (Figure 9) since the fraction of 127 I that remains in the water phase after batch experiments (at different pH) is low. The adsorption of iodide was high over the concentration range studied (1-30 ppb) as long as the concentration of iodate was low. The presence of iodate, a relatively large ion with low effective charge, seems to block adsorption of iodide even at iodate levels as low as 5ppb (Figure 10). In order to evaluate whether or not the method would be suitable for 129 I analysis, iodine trapped on the sorbents must be able to be removed. Consequently, after adsorption of iodine species, the activated charcoal was subjected to alkaline digestion or combustion at 900 0 C followed by extraction and back-extraction of iodine with CHCl3 and KHSO4 solution. The chemical yield of iodine following alkaline digestion, as measured by the added 38 125 I tracer, ranged from 46% to 56%. When activated charcoal from the batch
experiment was subjected to combustion at 900 0 C (see 2.7) the chemical yield of the 125 I tracer, ranged from 66% to70%. Compared with activated charcoal, DEAE 32 cellulose showed a slightly lower adsorption capacity of inorganic and organic iodine species (Tables 6-7). Fig. 9 Adsorption of iodine species from lake water onto activated charcoal at different pH. The concentration of iodine in lake water were 20.6ppb. The fraction of 127I that remains in the water phase after batch experiment (%) 50 40 30 20 10 0 The fraction of 127I that remains in the water phase after batch experiment (%) 15 10 5 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 pH Added iodide and iodate Fig. 10 Adsorption of iodine species onto activated charcoal as a function of concentrations of inorganic iodine species. The concentration of iodine in lake water was 9.2ppb. 39
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: a Fig. 8 Calibration curve for (a)
Page 43 and 44: Table 7 Adsorption of iodine specie
Page 45 and 46: numbers 11-14), which is about the
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
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of their contribution to the Baltic
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Fig. S-1 Sampling sites (the red so
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Fig. S-3 Vertical distribution of I
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Fig. S-5 Marine discharges function
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Fig.S-7 Relationship between I-129
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Table S-1 Results of I-129 and I-12
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S17
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Paper III Hansen,V., Yi, P., Hou, X
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conversion process between iodide a
Page 113 and 114:
Table 1 Analytical results of 129 I
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August April I-129 iodide ( 10 8 at
Page 117 and 118:
References Aldahan A, Kekli A, Poss
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Partition of iodine ( 129 I and 127
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Norway (Table 1). CTD-casts with ox
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5. Discussion 5.1. Separation of hu
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In the present study 40e60% of 129
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Hutta, M., Gora, R., 2003. Novel st
Page 129 and 130:
Analysis of 129 I and 127 I in arch
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et al., 2002). Due to the fact that
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espectively. The iodine was leached
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salinities in the same area. Apart
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North Sea. 129 I/ 127 I ratios in w
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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
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O’Dowd, C.; Jimenez, J. L.; Bahre
Page 147 and 148:
Iodine ( 129 I and 127 I) speciatio
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water in winter by molecular oxygen
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0.2 M KNO3. The effluent and the wa
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maximum values is at 0.03-0.06×10
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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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