The formation of iodide in inshore waters from the photochemical decomposition of dissolved organic iodine

Citation
Gtf. Wong et Xh. Cheng, The formation of iodide in inshore waters from the photochemical decomposition of dissolved organic iodine, MAR CHEM, 74(1), 2001, pp. 53-64
Citations number
54
Categorie Soggetti
Aquatic Sciences","Earth Sciences
Journal title
MARINE CHEMISTRY
ISSN journal
03044203 → ACNP
Volume
74
Issue
1
Year of publication
2001
Pages
53 - 64
Database
ISI
SICI code
0304-4203(200104)74:1<53:TFOIII>2.0.ZU;2-L
Abstract
Dissolved organic iodine (DOI) in inshore waters was decomposed by solar ir radiation. In the process, each mole of DOI was converted to about a mole o f iodide. The disappearance of DOI and the formation of iodide were directl y proportional to irradiation. The reaction could be expressed as a first-o rder reaction with respect to the concentration of DOI. The first-order rar e constant ranged between -0.2 and -0.6 m(2) kW(-1) h(-1). At the typical i rradiance of 0.5-1 kW m(-2) for a noon-day sun under a clear sky, the half- life of DOI relative to its photochemical decomposition was on the order of hours. This reaction provides an additional chemical pathway for the inter conversions among the dissolved iodine species in the oceans. It also allow s for alternative or complementary explanations for the observed photochemi cal production of iodide and methyl iodide in seawater. (C) 2001 Elsevier S cience B.V. All rights reserved.