Jf. Pankow et al., CALCULATED VOLATILIZATION RATES OF FUEL OXYGENATE COMPOUNDS AND OTHERGASOLINE-RELATED COMPOUNDS FROM RIVERS AND STREAMS, Chemosphere, 33(5), 1996, pp. 921-937
Large amounts of the ''fuel-oxygenate'' compound methyl-tert-butyl eth
er (MTBE) are currently being used in gasoline to reduce carbon monoxi
de and ozone in urban air and to boost fuel octane. Because MTBE can b
e transported to surface waters in various ways, established theory wa
s used to calculate half-lives for MTBE volatilizing from flowing surf
ace waters. Similar calculations were made for benzene as a representa
tive of the ''BTEX'' group of compounds (benzene, toluene, ethyl benze
ne, and the xylenes), and for tert-butyl alcohol (TBA). The calculatio
ns were made as a function of the mean flow velocity u (m/day), the me
an flow depth h (m), the ambient temperature, and the wind speed. In d
eep, slow-moving flows, MTBE volatilizes at rates which are similar to
those for the BTEX compounds. In shallow, fast-moving flows, MTBE vol
atilizes more slowly than benzene, though in such flows both MTBE and
benzene volatilize quickly enough that these differences may often not
have much practical significance. TEA was found to be essentially non
volatile from water.