Alcohols vapors

From Ethyl Alcohol. Some acetaldehyde is produced commercially by the catalytic oxidation of ethyl alcohol. The oxidation is carried out by passing alcohol vapors and preheated air over a silver catalyst at 480°C (98). 

Primary human skin irritation of tetradecanol, hexadecanol, and octadecanol is nil they have been used for many years ia cosmetic creams and ointments (24). Based on human testing and iudustrial experience, the linear, even carbon number alcohols of 6—18 carbon atoms are not human skin sensitizers, nor are the 7-, 9- and 11-carbon alcohols and 2-ethylhexanol. Neither has iudustrial handling of other branched alcohols led to skin problems. Inhalation hazard, further mitigated by the low vapor pressure of these alcohols, is slight. Sustained breathing of alcohol vapor or mist should be avoided, however, as aspiration hazards have been reported (25). 

The threshold limit value for ethyl alcohol vapor in air has been set at 1000 ppm for an 8-h time-weighted exposure by the ACGIH (1989 listing). The minimum identifiable odor of ethyl alcohol has been reported as 350 ppm. Exposure to concentrations of 5,000—10,000 ppm result in irritation of the eyes and mucous membranes of the upper respiratory tract and, if continued for an hour or more, may result in stupor or drowsiness. Concentrations of this latter order of magnitude have an intense odor and are almost intolerable to begin with, but most people can become acclimated to the exposure after a short time. Table 7 gives the effects of exposure to even heavier concentrations. 

Some authorities question whether dmnkeimess can result from the inhalation of ethyl alcohol vapors. Experience has demonstrated that in any event such intoxication is indeed rare (281). There is no concrete evidence that the inhalation of ethyl alcohol vapor will cause cirrhosis. Liver function is definitely impaired during alcohol intoxication (282), making the subject more susceptible to the toxic effects of chlorinated hydrocarbons. 

Spiritus, m. spirit, spirits, specif, alcohol, spiritusartig, a. spirituous, alcoholic. Splritus-beize, /. spirit mordant spirit stain, -blau, n. spirit blue, -brenner, m. (spirit) distiller alcohol burner, -brennerei, /. distillery, -dampf, m. alcohol vapor, -fa-bfik, /. spirit manufactory, distillery, -fass, n. spirit cask or barrel, -geruch, m. odor of spirits. -Industrie, /. spirit industry, distilling industry, -lack, m. spirit varnish, -lampe, /. spirit lamp, spiritusldslich, a. spirit-soluble. 

This mercury safety valve avoids all dangers which might result from the development of excess pressure within the system (Note 3). The temperature of the esterification mixture is kept at 105-110° and ethyl alcohol vapor is passed through until 500 cc. of distillate has been collected. This requires about three hours. The distillate consists of alcohol, water, and a little ether. 

Figure 3. Schematic representation of the selective synthesis of metal nanowires and nanoparticles by the Sintering Controlled Synthesis approach, (a) Mesoporous silica, (b) impregnation of mesoporous silica with metal ions, (c) addition of water/alcohol vapors and UV-irradiation, or wet H2-reduction, (d) formation of metal nanowires, (e) dry H2-reduction, (f) formation of metal nanoparticles.

Fig.4.8. Oscilloscope traces of variation of the electric conductivity of a ZnO sensor upon admission of isopropyl alcohol vapor to the vessel (the initial vapor pressure is 0.01 Torr) at the temperature of 390 C (/), 370 C (2), 350 C (5), 320 C (4), and upon admission of H2 at the temperature of 390 C (5).

Fig.4.9. Oscilloscope traces of temporal variation of the electric conductivity of a ZnO sensor for different initial pressures of the isopropyl alcohol vapor 5-2-t0-2 Torr (0, 3-6.10-2 (2), 1.65-10-1 0 and 3.25 10- Torr. The temperature of the ZnO film is 390 C.

Figure 4.8. displays oscillograms of evolution of the electric conductivity of the ZnO film in the process of catalytic dehydration of isopropyl alcohol at various temperatures of the catalyzer and equal portions of alcohol (5-10-2 Torr) admitted into the reaction cell. Experimental curves 1-4 are bell-shaped. We suppose that this fact is associated with two circumstances. On one hand, alcohol vapors dissociate on the oxide film producing hydrogen atoms. The jump in electric conductivity is caused by chemisorption of these hydrogen atoms on the film which plays a part of the sensor in this case. Chi the other hand, the drop in electric conductivity is caused by complete dissociation of the admitted portion of alcohol ( depletion of the source of hydrogen atoms) and by... 

Further investigations of the above discussed effects show that, at fixed temperature of the oxide film (catalyst), the jump in the electric conductivity first increases in amplitude, as the portion of alcohol vapor admitted into the vessel increases. On further increase of the admitted portion of alcohol, the jump amplitude reduces (starting with the pressure of 3.6-10 2 Torr). At the pressure of 3.2-10 Torr, the jump in the electric conductivity of the zinc oxide film is less pronounced. Finally, at still higher pressures, it disappears (Fig.4.9). This effect is not unexpected. On our mind, it is associated with the fact that, as the concentration of alcohol vapor increases, the sum of the rate of interaction of the vapor with adsorbed hydrogen atoms and the rate of surface recombination of hydrogen atoms at the time instant of production becomes higher than the chemisorption rate of these atoms. The latter is responsible for the increase of the electric conductivity of the semiconductor oxide film via the reaction... 

Should the acid tend to clog the delivery tube it is advisable to pass a slow stream of alcohol vapor through the esterification flask, in order to keep the tube open, even before the temperature of the esterification mixture has reached 1 io°. 

Methyl pyruvate has been prepared from the silver salt of pyruvic acid and methyl iodide,3 and from the free acid by the alcohol-vapor method without a catalyst.4 Pyruvic esters have also been prepared by the dehydrogenation of lactic acid esters.5... 

With alcohol vapor at 150° By refluxing at normal boiling point At 260° (autoclave)... 

Savelainen H, Pfaffli P Neurotoxicity of fur-fuiyl alcohol vapor in prolonged inhalation exposure. Environ Res 31 20 27, 1983... 

Kawai T, Yasugi T, Horiguchi S, et al Biological monitoring of occupational exposure to isopropyl alcohol vapor by urinalysis for acetone. Int Arch Occup Health 62 409-413, 1990... 

Alcohols. Methyl alcohol, and to a lesser extent ethyl alcohol, were used as freezing point depressants for many years. Their use now is minimal. When properly inhibited, alcohol-water solutions can be satisfactory coolants only under restricted conditions. Alcohol antifreezes fell into disuse because of their low boiling point (lower than that of water) and the danger of loss from boiling or evaporation. Alcohol volatilizes from hot surfaces much more readily than glycol coolant and can be a potential fire hazard. Methyl alcohol liquids are both flammable and poisonous. Methyl alcohol vapors are toxic when inhaled at high concentrations. 

The fact that the pressure reading at vacuum gauges (see Section 3.3) is sensitive to the type of gas involved can, to a certain extent, be utilized for leak detection purposes. Thus it is possible to brush or spray suspected leaks with alcohol. The alcohol vapors which flow into the device - the thermal conductivity and ionizablity of which will vary greatly from the same properties for air - will affect and change pressure indication to a greater or lesser extent. The availability of more precise, easy-to-use helium leak detectors has, however, rendered this method almost completely obsolete. 

Blood alcohol concentration (BAG) is often based not on an actual sample of blood but rather on the concentration of alcohol in a sample of breath (Figure 3.3). Alcohol is volatile, and, as described by Henry s law, there is a constant relationship between the amount of alcohol vapor found in a volume of air (breath sample) and the amount of alcohol found in a volume of liquid (blood). All breath-testing equipment uses the blood-breath ratio of 2,100 1 for alcohol. This means that the amount of alcohol found in 2,100 milliliters of breath is equivalent to the amount of alcohol found in 1 milliliters of blood. 

Seyama, M., Iwasaki, Y, Tate, A., and Sugimoto, L, Room-temperature ionic-liquid-incorporated plasma-deposited thin films for discriminative alcohol-vapor sensing, Chem. Mater., 18, 2656-2662, 2006. 

The submitters dried the ferZ-butyl alcohol by refluxing it over calcium hydride overnight and distillation in a moisture-free apparatus. The checkers found that stirring the ferf-butyl alcohol at 60-70° over calcium hydride for several hours and then distilling the alcohol, using an air condenser, is a satisfactory procedure. When the ferJ-butyl alcohol is refluxed, the alcohol vapors condense and solidify (m.p. 24-25°) in the reflux condenser and cause clogging. 

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