Kinetics and mechanism for the oxidation of 1,1,1‐trichloroethane

Abstract

The reaction mechanisms for oxidation of CH,CCI, and CC13CH2 radicals, formed in the atmospheric degradation of CH3CC1, have been elucidated. The primary oxidation products from these radicals are CH,CClO and CCl,CHO, respectively. Absolute rate constants for the reaction of hydroxyl radicals with CH3CC13 have been measured in 1 atm of Argon at 359, 376, and 402 K using pulse radiolysis combined with UV kinetic spectroscopy giving k(OH + CHThe effect of chlorine substitution on the reactivity of organic compounds towards OH radicals is discussed.

Evaluated kinetic and photochemical data for atmospheric chemistry: Volume IV – gas phase reactions of organic halogen species

“…The absolute and relative rate study of Barry et al (1994) supersedes the earlier studies of Nelson et al (1990), and . The three independent determinations of the rate coefficient by Barry et al (1994) are all lower than the absolute 298 K rate coefficient of , as is the most recent absolute room temperature rate coefficient of Talukdar et al (2001).…”

“…The absolute rate coefficients of and are lower than the data from the studies of Howard and Evenson (1976), Watson et al (1977), , , , , Nelson et al (1990), Jiang et al (1992) and Lancar et al (1993), in part due to the presence of reactive CH 2 =CCl 2 impurities in the CH 3 CCl 3 samples used (Jeongand Kaufman, 1979; and/or the formation of CH 2 =CCl 2 from thermal decomposition of CH 3 CCl 3 on surfaces . A unit-weighted least-squares analysis of the absolute rate coefficients of and …”

“…The preferred upper limit to the 298 K rate coefficient is based on the sole reported study of Nelson et al (1990), with the preferred upper limit being increased by a factor of 5 over that cited by Nelson et al (1990). …”

“…The preferred 298 K rate coefficient is based on the relative rate coefficient studies of and Nelson et al (1990), using the data presented in Table I and Figure 2 of and in Figure 5 of Nelson et al (1990), which are the same data-set. Note that Table I of Nelson et al (1990) cites a rate coefficient a factor of 7 lower [(9.1 ± 3.2) × 10 −15 cm 3 molecule −1 s −1 at 298 ± 3 K], inconsistent with the data presented in their Figure 5 and with the data presented in .…”

Comparison of UVC/S2O82− with UVC/H2O2 in terms of efficiency and cost for the removal of micropollutants from groundwater

“…Atrazine and cis-DCE can both be photolysed and they are targets for selective oxidation by sulfate radicals, due to their π-electrons in their double bonds (Antoniou et al, 2008;Antoniou et al, 2010b;Waldemer et al, 2007). MTBE and 1,4 dioxane are typically difficult treatment targets for most conventional water treatment methods and therefore are typically mentioned as target chemicals for UVC/H 2 O 2 (Burbano et al, 2002;Stefan and Bolton, 1998), while 1,1,1-trichlorethane is known to be resilient to chemical oxidation (Li et al, 2013;Nelson et al, 1990).…”