出版社：National Institute of Occupational Safety and Health
摘要：The velocity of spontaneous desorption of various solvents from carbon cloth K-filter TF-1500 (CC) housed in a diffusive sampler holder was examined. Among the 16 most popular organic solvents (acetone, benzene, butyl acetate, ethanol, ethyl acetate, n-hexane, isopropyl alcohol, methanol, methyl ethyl ketone, methyl isobutyl ketone, styrene, tetrachloroethylene, toluene, 1, 1, 1-trichloroethane, trichloroethylene and m-xylene), the desorption half-time (T1, 2) was various depend-ing on the solvent and was shortest with methanol (57 min) followed by ethanol (20 h) and acetone (38 h). As T1, 2 values observed were mostly larger than 24 h, it was possible to conclude that diffusive sampling with CC is generally applicable to the exposure monitoring of a wide range of solvents. The application to methanol is, however, practically impossible due to its rapid spontaneous desorp-tion. The solvent with short T1, 2 of spontaneous desorption can be best predicted from log (n-octanol/water partition coefficient) [log (Po/w)] ; a solvent with log (Po/w) of less than zero will have T1, 2 of less than 24 h, and diffusive sampling may not be applicable to monitoring of such solvents. Packing of CC in aluminum foil immediately after the termination of exposure and storage at 4°C jointly im-proved the preservation of the impregnated solvents so that no significant loss was detected for any solvent tested except for methanol in 4 days.
关键词：Carbon cloth;Desorption halr-time;Diffusive sampling;Organic;solvent;Prediction of desorption;Spontaneous desorption
