ABSTRACT
CASRN: 75-65-0; DOT: 1120; DOT label: Flammable liquid; molecular formula: C4H10O; FW: 74.12; RTECS: EO1925000; Merck Index: 12, 1577 Physical state, color, and odor: Colorless liquid or crystals with a camphor-like odor. A detection odor threshold concentration of 2,900 mg/m3 (957 ppmv) was experimentally determined by Dravnieks (1974). In a later study, Nagata and Takeuchi (1990) reported an odor threshold concentration 220 ppbv. Melting point (°C): 25.5 (Weast, 1986) Boiling point (°C): 82.32 (Tu et al., 2001) Density (g/cm3): 0.78114 at 25.00 °C, 0.77551 at 30.00 °C (Nikam et al., 1998a) 0.78049 at 25.00 °C, 0.77573 at 30.00 °C, 0.77020 at 35.00 °C, 0.76484 at 40.00 °C, 0.75941 at
45.00 °C (Martinez et al., 2000a) 0.77502 at 30.00 °C (Nikam et al., 2000) Diffusivity in water (x 10-6 cm2/sec at 25 °C): 8.7 (Hao and Leaist, 1996) 8.8 (Tominaga and Matsumoto, 1990) Dissociation constant, pKa: ≈19 (Gordon and Ford, 1972) Flash point (°C): 16.7 (closed cup, Eastman, 1995) 4 (Aldrich, 1990) Lower explosive limit (%): 2.4 (NIOSH, 1997) Upper explosive limit (%): 8.0 (NIOSH, 1997) Entropy of fusion (cal/mol⋅K): 5.44 (Yalkowsky and Valvani, 1980) Heat of fusion (kcal/mol): 1.587 (quoted, Riddick et al., 1986)
0.112 at 0 °C, 1.44 at 35 °C (headspace-GC, Arp and Schmidt, 2004) 3.77 at 20 °C (equilibrium method, Kaneko et al., 2000) 1.19 at 25 °C (Butler et al., 1935) 1.44 at 25 °C (Snider and Dawson, 1985) 90.7 at 25 °C (thermodynamic method-GC/UV spectrophotometry, Altschuh et al., 1999) 1.22 at 25 °C (static headspace-GC, Merk and Riederer, 1997) Ionization potential (eV): 9.70 (NIOSH, 1997) Soil organic carbon/water partition coefficient, log Koc: Unavailable because experimental methods for estimation of this parameter for alcohols are lacking in the documented literature. However, its miscibility in water and low Kow suggest its adsorption to soil will be nominal (Lyman et al., 1982). Octanol/water partition coefficient, log Kow: 0.37 (shake flask-GLC, Hansch and Anderson, 1967) 0.59 (Yonezawa and Urushigawa, 1979) Solubility in organics: In mole fraction at 4.5 °C: 0.376 in triethylenetetramine, 0.364 in hexamethylenediamine (Copley et al., 1941) Solubility in water: Miscible (NIOSH, 1997; Palit, 1947). A saturated solution in equilibrium with its own vapor had a concentration of 316.2 g/L at 25 °C (Kamlet et al., 1987). Vapor pressure (mmHg): 30.6 at 20.00 °C, 42.0 at 25.00 °C, 56.9 at 30.00 °C, 76.3 at 35.00 °C, 102.3 at 40.00 °C, 133.8 at 45.00 °C, 174.3 at 50.00 °C, 224.2 at 55.00 °C, 285.2 at 60.00 °C, 358.2 at 65.00 °C, 447.3 at 70.00 °C, 553.2 at 75.00 °C, 679.4 at 80.00 °C, 826.3 at 85.00 °C, 996.2 at 90.00 (Parks and Barton, 1928) Environmental fate: Biological. Bridié et al. (1979) reported BOD and COD values of 0.02 and 2.49 g/g using filtered effluent from a biological sanitary waste treatment plant. These values were determined using a standard dilution method at 20 °C for a period of 5 d. The ThOD for tert-butyl alcohol is 2.59 g/g. In activated sludge inoculum, 98.5% COD removal was achieved. The average rate of biodegradation was 30.0 mg COD/g⋅h (Pitter, 1976). Bradley et al. (1999) studied the degradation of tert-butyl alcohol by indigenous microorganisms in stream-bed sediments from underground gasoline spill sites in Laurens, SC (Laurens) and Charleston, SC (Oasis). Under aerobic conditions, the amount of tert-butyl alcohol mineralizing to carbon dioxide after 27 d was 70% in both Laurens and Oasis sediments. After 80 d, the amount of mineralization reached an asymptiotic level of approximately 84%. No mineralization of tert-butyl alcohol was observed under strictly anaerobic conditions. Photolytic. Wallington (1988c) reported a rate constant of 1.07 x 10-12 cm3/molecule⋅sec at 298 K. Based on an atmospheric OH concentration of 1.0 x 106 molecule/cm3, the reported half-life of tert-butyl alcohol is 8.6 d (Grosjean, 1997). Chemical/Physical. May react with strong mineral acids (e.g., hydrochloric) or oxidizers releasing isobutylene (NIOSH, 1997).
