Volatilization | The Henry's Law constant for n-butane is estimated as 0.95 atm-cu m/mole(SRC) based upon its vapor pressure, 1820 mm Hg(1), and water solubility, 61.2 mg/l(2). This Henry's Law constant indicates that n-butane is expected to volatilize rapidly from water surfaces(3). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as 50 minutes(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(3) is estimated as 3.0 days(SRC). n-Butane's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). n-Butane is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(1). Literature: (1) Riddick JA et al; Organic Solvents: Physical Properties and Methods of Purification, Techniques of Chemistry 4th ed., New York, NY: Wiley-Interscience Vol 2, p. 78-80 (1986) (2) McAuliffe C; Nature, 200: 1092-3 (1963) (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods New York, NY: McGraw-Hill p. 15-15 to 15-29 (1982) |
Soil Adsorption | The Koc of n-butane is estimated as 900(SRC), using a measured log Kow of 2.89(1) and a regression-derived equation(2). According to a classification scheme(3), this estimated Koc value suggests that n-butane is expected to have low mobility in soil. Literature: (1) Hansch C et al; Exploring QSAR. Hydrophobic, Electronic, and Steric Constants. ACS Prof Ref Book. Heller SR, consult. ed., Washington, DC: Amer Chem Soc p. 10 (1995) (2) US EPA; Estimation Program Interface (EPI) Suite. Ver. 4.1. Nov, 2012. Available from, as of Nov 20, 2013: http://www.epa.gov/oppt/exposure/pubs/episuitedl.htm (3) Swann RL et al; Res Rev 85: 17-28 (1983) |
Vapor Pressure | Pressure | Reference |
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1820 mm Hg at 25 deg C | Riddick, J.A., W.B. Bunger, Sakano T.K. Techniques of Chemistry 4th ed., Volume II. Organic Solvents. New York, NY: John Wiley and Sons., 1985., p. 78 |
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