Atmospheric chemistry of perfluorinated aldehyde hydrates (n-CxF2x+1CH(OH)2, x=1, 3, 4):: Hydration, dehydration, and kinetics and mechanism of Cl atom and OH radical initiated oxidation
Atmospheric chemistry of perfluorinated aldehyde hydrates (n-CxF2x+1CH(OH)2, x=1, 3, 4):: Hydration, dehydration, and kinetics and mechanism of Cl atom and OH radical initiated oxidation
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DOI：
10.1021/jp060404z
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发表时间：
2006-08-17
影响因子：
2.9
通讯作者：
Ellis, D. A.
中科院分区：
文献类型：
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作者：
Andersen, M. P. Sulbaek;Toft, A.;Ellis, D. A.
采用烟雾室/傅里叶变换红外（FTIR）技术测量了（Cl+CxF2x+1CH（OH）（2））（x = 1，3，4）=（5.84 +/- 0.92）x 10（-13）和k（OH+ CxF 2x +1CH（OH）（2））（1.22 +/- 0.26）x 10（-13）cm（3）分子（-1）s（-1）在700 Torr的N-2或空气中，296 +/- 2 K。在700托空气中，Cl引发的CF 3CH（OH）（2）的氧化以101 +/-6%的摩尔产率产生CF 3COOH。本文报道了CxF_（2x）+1CH（OH）（2）（x = 1，3，4）的红外光谱。确定了CF_3CHO气相水合反应的上限k（CF_3CHO + H_2O）< 2 × 10 ~（-23）cm ~（3）molecule ~（-1）s ~（-1）。使CF 3CHO/空气混合物鼓泡通过液态水导致在通过鼓泡器所花费的约2秒内> 80%的CF 3CHO转化成水合物。这些结果表明，OH自由基引发的CxF 2x +1CH（OH）（2）水合物的氧化可能是环境中全氟羧酸的重要来源。
Smog chamber/Fourier transform infrared (FTIR) techniques were used to measure k(Cl+CxF2x+1CH(OH)(2)) (x = 1, 3, 4) = (5.84 +/- 0.92) x 10(-13) and k(OH+ CxF2x+1CH(OH)(2)) (1.22 +/- 0.26) x 10(-13) cm(3) molecule(-1) s(-1) in 700 Torr of N-2 or air at 296 +/- 2 K. The Cl initiated oxidation of CF3CH(OH)(2) in 700 Torr of air gave CF3COOH in a molar yield of 101 +/- 6%. IR spectra of CxF2x+1CH(OH)(2) (x = 1, 3, 4) were recorded and are presented. An upper limit of k(CF3CHO+H2O) < 2 x 10(-23) cm(3) molecule(-1) s(-1) was established for the gas-phase hydration of CF3CHO. Bubbling CF3CHO/air mixtures through liquid water led to > 80% conversion of CF3CHO into the hydrate within the approximately 2 s taken for passage through the bubbler. These results suggest that OH radical initiated oxidation of CxF2x+1CH(OH)(2) hydrates could be a significant source of perfluorinated carboxylic acids in the environment.