Study On Iodine Species In Atmosphere

The topic of the research is the collection of various iodine species in atmosphere by speciation air sampler, and the iodine determination using hydrolysis-catalytic spectrophotometry. A specialized iodine species sampling outfit inlaying untreated glass fiber filter, NaOH-impregnated glass fiber filter, tetrabutyl ammonium hydroxide-impregnated glass fiber filter and activated carbon-impregnated glass fiber filter sequently designed to collect various iodine species in atmosphere. Particulate iodine, HI and I2, HOI, organic-bound iodine were collected in order of filters with the circulating of air through sampler. Hydrolysis-arsenic and cerium catalytic spectrophotometry method were employed to determine the content of four iodine species. In addition a batch of Masson Pine was sampled; the iodine contents in the organs of Masson Pine were also measured.In the research, the percentage content of various iodine species in atmosphere and the content of iodine in the organs of Masson Pine from Zhejiang, Jiangxi, Shandong, Guizhou provinces were determined. Within the distance of 0-80 km from the coastline, the percentage content of organic-bound iodine in atmosphere declines gradually with the increase of distance from the sea; but the variation of particulate iodine displays opposite rule compared with organic-bound iodine, so do the percentage contents of HI, I2 and HOI. However, the contents of HI, I2 and HOI are rare 500 km away from the sea. In carbonate bedrock areas, the content of particulate iodine is significantly higher than that in granite bedrock areas, yet the content of organic-bound iodine is remarkably lower than that in granite bedrock areas. The order of the iodine contents in Masson Pine organs is bark> old leaf> tender leaf> twig.