FIELD: water purification.
SUBSTANCE: invention can be used in the purification of wastewater containing radiographic contrast agents. A method for the extraction of molecular iodine from an aqueous solution containing an iodine-containing aromatic compound and an iodine-containing inorganic compound containing iodide-ions includes stages, at which iodine of the mentioned iodine-containing aromatic compound is converted into molecular iodine, and the mentioned molecular iodine is collected. At the same time, pH of the aqueous solution containing the iodine-containing aromatic compound subjected to the conversion is 1 or less, and a mass ratio between iodide-ions and iodine contained in the aromatic compound in the aqueous solution is at least 0.5 or more.
EFFECT: invention allows for providing high level of iodine extraction from wastewater.
19 cl, 11 ex
