Iodine speciation in the Nile River estuary

Abdel-Moati, Mohamed A.

doi:10.1016/s0304-4203(99)00003-1

Cited by 43 publications

(23 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These volatile organic iodine species were also suggested to contribute to ozone depletions in the lower stratosphere, particularly the marine boundary layer [50][51] and cloud condensation in the lower troposphere [52]. In fresh water, such as rivers, lakes and rain, iodine exists also as iodide, iodate and organic iodine, but the relative concentration of organic iodine is higher compared to seawater [53][54][55][56].…”

Section: Speciation Of Iodine In Watermentioning

confidence: 99%

A review on speciation of iodine-129 in the environmental and biological samples

Hou

Hansen

Aldahan

et al. 2009

Analytica Chimica Acta

336

309

View full text Add to dashboard Cite

Section: Speciation Of Iodine In Watermentioning

confidence: 99%

A review on speciation of iodine-129 in the environmental and biological samples

Hou

Hansen

Aldahan

et al. 2009

Analytica Chimica Acta

336

309

View full text Add to dashboard Cite

“…Its form depends partly on pH and the redox status of the surrounding environment; thus iodide is reported as the most prevalent form of iodine in river waters while iodate is most common in the oceans (Smith and Butler, 1979;Abdel-Moati, 1999). In rainwater a mix of species including iodate, iodide and organic iodine species have been reported (Gilfedder et al, 2008).…”

Section: Introductionmentioning

confidence: 99%

Iodine dynamics in soils

Shetaya

Young

Watts

et al. 2012

Geochimica et Cosmochimica Acta

137

118

View full text Add to dashboard Cite

We investigated changes in iodine ( 129 I) solubility and speciation in nine soils with contrasting properties (pH, Fe/Mn oxides, organic carbon and iodine contents), incubated for nine months at 10 and 20°C. The rate of 129 I sorption was greater in soils with large organic carbon contents (%SOC), low pH and at higher temperatures. Loss of iodide (I À ) from solution was extremely rapid, apparently reaching completion over minutes-hours; iodate (IO À 3 ) loss from solution was slower, typically occurring over hours-days. In all soils an apparently instantaneous sorption reaction was followed by a slower sorption process for IO À 3 . For iodide a faster overall reaction meant that discrimination between the two processes was less clear. Instantaneous sorption of IO À 3 was greater in soils with high Fe/Mn oxide content, low pH and low SOC content, whereas the rate of time-dependent sorption was greatest in soils with higher SOC contents. Phosphate extraction (0.15 M KH 2 PO 4 ) of soils, $100 h after 129 I spike addition, indicated that concentrations of sorbed inorganic iodine ( 129 I) were very low in all soils suggesting that inorganic iodine adsorption onto oxide phases has little impact on the rate of iodine assimilation into humus. Transformation of dissolved inorganic 129 IO À 3 and 129 I À to sorbed organic forms was modelled using a range of reactionand diffusion-based approaches. Irreversible and reversible first order kinetic models, and a spherical diffusion model, adequately described the kinetics of both IO À 3 and I À loss from the soil solution but required inclusion of a distribution coefficient (k d ) to allow for instantaneous adsorption. A spherical diffusion model was also collectively parameterised for all the soils studied by using pH, soil organic carbon concentration and combined Fe + Mn oxide content as determinants of the model parameters (k d and D/r 2 ). The kinetic model parameters were not directly related to a single soil parameter; inclusion of pH, SOC, oxide content and temperature was necessary to describe the observed behaviour. From the temperature-dependence of the sorption data the activation energy (E a ) for 129 IO À 3 transformation to organic forms was estimated to be $43 kJ mol À1 . The E a value was independent of %SOC and was consistent with a reaction mechanism slower than pore diffusion or physical adsorption, but faster than most surface reactions.

show abstract

“…The presence of other iodine-containing species in the electropherogram may be due to the presence of large amounts of natural organic matter. Moreover, results obtained by some other authors confirmed the existence of a large number of iodine species in natural waters [18,28,29,42]. Future studies will be performed to identify and determine other iodine species present in river water samples.…”

Section: Determination Of Iodophenols In River Waters and Recovery Stmentioning

confidence: 53%

Fast speciation analysis of iodophenol compounds in river waters by capillary electrophoresis‐inductively coupled plasma‐mass spectrometry with off‐line solid‐phase microextraction

et al. 2004

View full text Add to dashboard Cite

An analytical methodology for the fast separation and determination of iodophenol species in natural water samples was developed using capillary electrophoresis (CE) coupled to inductively coupled plasma-mass spectrometry (ICP-MS). Based on the element-specific and highly sensitive detection provided by ICP-MS, the methodology has been applied to the analysis of 2-iodophenol, 4-iodophenol, and 2,4,6-triiodophenol. The use of solid-phase microextraction (SPME), after proper optimization, improved the signal by a factor of 100 leading to detection limits in the sub microg.L(-1). Different desorption conditions of iodophenol compounds from the SPME microfiber were studied to achieve the optimum preconcentration factor and best analytical performance. Different CE conditions were studied to achieve complete baseline separation of iodophenols in short migration times. Three different CE buffer systems were evaluated using ICP-MS detection. A buffer solution containing 20 mmol.L(-1) 3-(cyclohexylamino)-1-propanesulfonic acid (CAPS) and an applied potential of +22 kV were finally selected leading to a maximum separation time of 6.6 min. A relative standard deviation (%RSD) of about 5.0% for ten consecutive determinations was obtained. Finally, the speciation methodology developed was utilized for the determination of iodophenol compounds in natural water samples.

show abstract

Iodine speciation in the Nile River estuary

Cited by 43 publications

References 44 publications

A review on speciation of iodine-129 in the environmental and biological samples

A review on speciation of iodine-129 in the environmental and biological samples

Iodine dynamics in soils

Fast speciation analysis of iodophenol compounds in river waters by capillary electrophoresis‐inductively coupled plasma‐mass spectrometry with off‐line solid‐phase microextraction

Contact Info

Product

Resources

About