1,2-DICHLOROETHANE

Note: 1,2-Dichloroethane may contain alkylamines (0.1 wt %) to inhibit decomposition during storage. CASRN: 107-06-2; DOT: 1184; DOT label: Flammable liquid; molecular formula: C2H4Cl2; FW: 98.96; RTECS: KI0525000; Merck Index: 12, 3843 Physical state, color, and odor: Clear, colorless, oily liquid with a pleasant, chloroform-like odor. The average least detectable odor threshold concentrations in water at 60 °C and in air at 40 °C were 12 and 52 mg/L, respectively (Alexander et al., 1982). Experimentally determined detection and recognition odor threshold concentrations were 25 mg/m3 (6 ppmv) and 165 mg/m3 (41 ppmv), respectively (Hellman and Small, 1974). Melting point (°C): -35.3 (Weast, 1986) -35 (Acros Organics, 2002) Boiling point (°C): 82.85 (Young and Nelson, 1932) 83.55 °C (Krishnaiah and Surendranath, 1996) Density (g/cm3): 1.26000 at 15 °C (quoted, Standen, 1964) 1.2350 at 20 °C (Qun-Fang et al., 1997) 1.2464 at 25.00 °C (Vijaya Kumar et al., 1996) 1.23828 at 30.00 °C (Krishnaiah and Surendranath, 1996) Diffusivity in water (x 10-5 cm2/sec): 1.01 at 20 °C using method of Hayduk and Laudie (1974) Flash point (°C): 13.3 (Fordyce and Meyer, 1940; NIOSH, 1997) 12-15 (Worthing and Hance, 1991) Lower explosive limit (%): 6.2 (NIOSH, 1997) Upper explosive limit (%): 16 (NIOSH, 1997) Heat of fusion (kcal/mol): 2.112 (quoted, Riddick et al., 1986)

11.1 at 25 °C (gas stripping-GC, Warner et al., 1987) 13.2 at 25 °C (static headspace-GC, Welke et al., 1998) 9.8 at 25 °C (Dilling, 1977) 9.09 at 20 °C (Pearson and McConnell, 1975) 12.2 at 25 °C (EPICS-GC, Chatkun Na Ayuttaya et al., 2001) 11.90 at 25 °C (Hoff et al., 1993) 22.5 at 37 °C (Sato and Nakajima, 1979) 11.7, 13.0, 14.7, 14.1, and 17.4 at 10, 15, 20, 25, and 30 °C, respectively (EPICS, Ashworth et al.,

1988) 10, 15, 18, and 22 at 20, 30, 35, and 40 °C, respectively (Tse et al., 1992) Distilled water: 3.43, 4.48, 4.12, 7.47, and 10.09 at 2.0, 6.0, 10.0, 18.2, and 25.0 °C, respectively;

natural seawater: 5.52 and 11.3 at 6.0 and 25.0 °C, respectively (EPICS, Dewulf et al., 1995) 9.47 at 20.00 °C (inert gas stripping, Hovorka and Dohnal, 1997) 11.8 at 25.0 °C (mole fraction ratio-GC, Leighton and Calo, 1981) 9.06 at 20.0 °C, 18.3 at 35.0 °C, 31.5 at 50.0 °C (equilibrium static cell, Wright et al., 1992) 11.24 at 30 °C (headspace-GC, Sanz et al., 1997) Interfacial tension with water (dyn/cm): 28.4 at 25 °C (quoted, Freitas et al., 1997) Ionization potential (eV): 11.05 (NIOSH, 1997) 11.12 ± 0.05 (Franklin et al., 1969) Bioconcentration factor, log BCF: 0.30 (bluegill sunfish, Veith et al., 1980) Soil organic carbon/water partition coefficient, log Koc: 1.279 (Willamette silt loam, Chiou et al., 1979) 1.34 (Jury et al., 1990) 1.88 (Lincoln sand, Wilson et al., 1981) 1.64, 1.65, 1.64, 1.68, 1.70, 1.65, and 1.68 at 2.3, 3.8, 6.2, 8.0, 13.5, 18.6, and 25.0 °C,

respectively, for a Leie River (Belgium) clay (Dewulf et al., 1999a) Octanol/water partition coefficient, log Kow: 1.48 (Konietzko, 1984) 1.45 at 23 °C (shake flask-LSC, Banerjee et al., 1980) 1.51, 1.51, and 1.53 at 25, 35, and 50 °C, respectively (GLC, Bhatia and Sandler, 1995) 1.43, 1.42, 1.47, 1.44, 1.50, and 1.46 at 2.2, 6.0, 10.0, 14.1, 18.7, and 24.8 °C, respectively (shake

flask-GC, Dewulf et al., 1999a) Solubility in organics: Miscible with chloroform, ethanol, ether (U.S. EPA, 1985), and tetrachloroethylene Solubility in water: In g/kg: 9.22 at 0 °C, 8.85 at 10 °C, 8.69 at 20 °C, 8.94 at 30 °C (Rex, 1906) In mg/kg: 10,554 at 10 °C, 8,467 at 20 °C, 10,467 at 30 °C (shake flask-GC, Howe et al., 1987) 8,300 mg/L at 25 °C (gas stripping, Warner et al., 1987) 7,986 mg/L at 25 °C (shake flask-LSC, Banerjee et al., 1980) In mg/kg: 9,000 at 0 °C, 8,500 at 10 °C, 8,400 at 20 °C, 8,700 at 30, 9,100 at 40, 9,900 at 50 °C

8,650 mg/kg at 25 °C (shake flask-interferometer, Gross, 1929) 8,800 mg/L at 20 °C (McConnell et al., 1975) 8,450 mg/L at 20 °C (Chiou et al., 1979) 0.873 wt % at 0 °C (Konietzko, 1984) In wt %: 0.82 at 0 °C, 0.77 at 9.3 °C, 0.72 at 19.7 °C, 0.81 at 29.7 °C, 0.98 at 39.4 °C, 1.06 at 50.3

°C, 1.08 at 61.0 °C, 1.13 at 70.6 °C, 1.06 at 80.7 °C (shake flask-GC, Stephenson, 1992) 8,720 mg/kg at 15 °C, 9,000 mg/kg at 30 °C (shake flask-interferometer, Gross and Saylor, 1931) 8,524 mg/L at 25 °C (quoted, Howard, 1990) 3,506 mg/L at 30 °C (vapor equilibrium-GC, McNally and Grob, 1984) 1.56 x 10-3 at 25 °C (mole fraction, inert gas stripping-GC, Li et al., 1993) 8,690 mg/L at 25 °C (Cowen and Baynes, 1980) Vapor density: 4.04 g/L at 25 °C, 3.42 (air = 1) Vapor pressure (mmHg): 87 at 25 °C (ACGIH, 1986) 78.7 at 20 °C (quoted, Howard, 1990) 82 at 25 °C (quoted, Nathan, 1978) Environmental fate: Biological. Methanococcus thermolithotrophicus, Methanococcus deltae, and Methanobacterium thermoautotrophicum metabolized 1,2-dichloroethane releasing methane and ethylene (Belay and Daniels, 1987). 1,2-Dichloroethane showed slow to moderate biodegradative activity with concomitant rate of volatilization in a static-culture flask-screening test (settled domestic wastewater inoculum) conducted at 25 °C. At concentrations of 5 and 10 mg/L, percent losses after 4 wk of incubation were 63 and 53, respectively. At a substrate concentration of 5 mg/L, 27% was lost due to volatilization after 10 d (Tabak et al., 1981). Photolytic. Titanium dioxide suspended in an aqueous solution and irradiated with UV light (λ = 365 nm) converted 1,2-dichloroethane to carbon dioxide at a significant rate (Matthews, 1986). The rate constant for the reaction of 1,2-dichloroethane and OH radicals in the atmosphere at 300 K is 1.3 x 10-11 cm3/molecule⋅sec (Hendry and Kenley, 1979). At 296 K, a photooxidation rate constant of 2.2 x 10-13 cm3/molecule⋅sec was reported for the reaction with OH radicals resulting in a half-life of 1.7 months (Howard and Evenson, 1976). Chemical/Physical. Anticipated products from the reaction of 1,2-dichloroethane with ozone or OH radicals in the atmosphere are chloroacetaldehyde, chloroacetyl chloride, formaldehyde, and ClHCHO (Cupitt, 1980). Hydrolysis of 1,2-dichloroethane under alkaline and neutral conditions yielded vinyl chloride and ethylene glycol, respectively, with 2-chloroethanol, and ethylene oxide forming as the intermediates under neutral conditions (Ellington et al., 1988; Jeffers et al., 1989; Kollig, 1993). The reported hydrolysis half-life in distilled water at 25 °C and pH 7 is 72.0 yr (Jeffers et al., 1989), but in a 0.05 M phosphate buffer solution the hydrolysis half-life is 37 yr (Barbash and Reinhard, 1989). Based on a measured hydrolysis rate constant of 1.8 x 10-8 at 25 °C and pH 7, the half-life is 71.5 yr (Jeffers and Wolfe, 1996). In an aqueous solution, 1,2-dichloroethane reacted with hydrogen sulfide ions forming 1,2dithioethane (Barbash and Reinhard, 1989). The volatilization half-life of 1,2-dichloroethane (1 mg/L) from water at 25 °C using a shallowpitch propeller stirrer at 200 rpm at an average depth of 6.5 cm was 28.0 min (Dilling, 1977). At 600 °C, 1,2-dichloroethane decomposes to vinyl chloride and hydrogen chloride (NIOSH, 1997).