Importance of Automobile Exhaust Catalyst Emissions for the Deposition of Platinum, Palladium, and Rhodium in the Northern Hemisphere

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• 作者：Sebastien Rauch ; Harold F. Hemond ; Carlo Barbante ; Masanori Owari ; Gregory M. Morrison ; Bernhard Peucker-Ehrenbrink ; and Urban Wass
• 刊名：Environmental Science & Technology
• 出版年：2005
• 出版时间：November 1, 2005
• 年：2005
• 卷：39
• 期：21
• 页码：8156 - 8162
• 全文大小：320K
• 年卷期：v.39,no.21(November 1, 2005)
• ISSN：1520-5851

文摘

An estimated 500 million vehicles worldwide are equippedwith an exhaust catalyst that uses platinum groupelements (PGE) as the main active components and thuscontribute to global PGE emissions. Although PGE emittedfrom automobile exhaust catalysts were first believed toremain in the roadside environment, we propose here thatfine PGE-containing particles in automobile exhaust haveresulted in a widespread distribution of emitted PGE. Regionaland long-range transport of PGE from automobile exhaustcatalysts is supported by elevated PGE deposition inboth a peat bog located 250 m from traffic and in centralGreenland, respectively. Russian smelters were alsofound to contribute to PGE contamination in central Greenland.Deposition rates estimated for the roadside environment,the peat bog, and central Greenland were used to providea first estimate of PGE deposition in the northernhemisphere. The results show that deposition of regionallyor long-range transported PGE accounts for a largefraction of total PGE deposition, and PGE deposition inthe roadside environment represents less than 5% of thetotal deposition. Transport at the regional and global scalesrepresents an important component in the environmentalcycle of emitted PGE and needs to be further studied tofully assess the environmental fate of PGE from automobileexhaust catalysts.