Alcohol vapors, condensation

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. 

The term still is applied only to the vessel in which liquids are boiled during distillation, but the term is sometimes applied to the entire apparatus, including the fractionating column, the condenser, and the receiver in which the distillate is collected. If a water and alcohol distillate is returned from the condenser and made to drip down through a long column onto a series of plates, and if the vapor, as it rises to the condenser, is made to bubble through this liquid at each plate, the vapor and liquid will interact so that some of the water in the vapor condenses and some of the alcohol in the liquid vaporizes. The interaction at each plate is equivalent to a redistillation. This process is referred to by several names in the industry namely rectification, fractionation, or fractional distillation. 

Barbitone. (Barbital, veronal, 5 5-diethyl malonyl urea) The exclusion of water is also paramount in this step (use drying tubes, etc.). 30 kilos of dry urea and 76.5 kilos of the above malonate (dry diethyl diethyl malonate) are placed in the reaction vessel and stirred very well. To this mixture is added a solution of hot (75°) sodium ethylate (18 kilos of clean sodium metal in 270 liters of dry ethanol) and the mixture is brought to a boil with good stirring. The alcohol is removed with the boiling action (the reaction vessel is equipped with a slanted vapor condenser) and the mixture becomes more viscous. The alcohol (ethanol) is distilled out completely and the heat is then removed. The residue left behind should be a creamy white powder. 

Several times when benzoin was being prepared, the condensation took place and was complete after boiling five to ten minutes or even less, the product separating out in the hot solution with evolution of heat. The yield under these conditions was always good and the color better than when the reaction took a longer time. The cause of this occasional rapid reaction was not discovered, but it was probably due to inoculation with a little benzoin in certain of the experiments. When it takes place as just described, the flask and efficient condenser used will be sufficient to condense the sudden, rapid evolution of alcohol vapors caused by the heat of crystallization of the benzoin. 

DISTILLATION A heat-dependent process used to produce alcoholic beverages, such as whiskey, rum, and vodka. In this process, a fermented mash (of grains, vegetables, or fruits) is heated in a boiler, causing the alcohol to evaporate. The alcohol vapors are then collected and cooled in a condenser to produce the beverage. 

A cloud chamber contains supercooled supersaturated alcohol vapor. If you send any tiny charged object into this vapor that charged object will cause ions to form in the vapor. These ions serve as places on which the vapor can condense (turn to liquid) and form tiny little "clouds." If the charged object moves really fasp it vvdll leave trails of tiny clouds which form tracks. 

The alcohol is first vaporized by passing it through coils heated to 80° to 90° C. and through a copper tube containing the catalyst and heated in a bath of fused potassium nitrate. The reaction products then pass through coolers where the water and alcohol are condensed while the ethylene is washed and led into storage vessels. 

Fig. 9 Decrease of friction force upon environment change from ambient humid air to saturated alcohol vapor. The friction signals are normalized to the initial friction signals measured in ambient air for each experiment to minimize errors because of tip diameter variance in each measurement and emphasize the relative change because of condensed alcohol layer formation. The inset shows temporal changes of friction force upon sudden environment changes. The applied normal signal is kept constant at 75 nN. (View this art in color at WWW. dekker. com.)...

One mechanism that has been proposed for the conversion of ethyl alcohol to butadiene in the vapor phase consists of three steps (a) dehydration of the ethyl alcohol b) dehydrogenation of the ethyl alcohol (c) condensation of the ethylene and acetaldehyde in (a) and (b) to give butadiene, C Hg. At 400 . the following information is available for the three steps ... 

The vapor leaving the exhausting column to pass to the heater is substantially in equilibrium with the liquid on the top plate of the column. It is partially condensed in the heater, enriched in its alcohol content, and then passes to the condenser where it is completely condensed. The portion of the vapor condensed in the heater is returned to the top plate of the column together with a controlled portion of the vapor condensed in the condenser, from the regulating bottle E. The distillate flows, through the tester F where its quantity and specific gravity may be measured, to the storage tank G. The water supply for the condenser is obtained from the constant level feed tank N. ... 

A similar method (3) for maturing potable alcoholic liquors is to mix the vapors from a pot still with heated air, subdivide the mixture into narrow streams, and pass this through a narrow conduit heated to about 150° C. The streams are joined and the treated vapors condensed. The heated metal walls are supposed to act catalytically to produce the desired result. 

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