Vodka still

Figure 1.3 Vodka still Lithuania, 2003. Device to separate alcohol from water.

If the liquid is full of particulates, like starch when 1 boil pasta, then the flooding will occur at a lower vapor velocity. When my pasta pot floods over, 1 turn down the heat. If my vodka still is flooding, then more heat will increase, and not decrease, the water content of my vodka bottle. By checking how the heat added to my still is affecting the proof of the vodka, I could determine the optimum amount of wood to burn under the still. 

As you read the subsequent chapters in this book, please recall the picture of the vodka still. Keep in mind that the origin of the reflux is the vapor generated from burning firewood beneath the big can. This concept is the key to understanding how distillation towers function. You cannot have more reflux without increasing your reboiler duty, unless you are willing to sacrifice the overhead product yield. And if extra reflux results in more heavy components in the overhead, the trays are flooding. 

In spite of a decline over the past 50 years, whiskeys are still the most popular distilled alcoholic beverage group in the United States (Table 1) (1). However, vodka consumption has increased significandy to 22% of total distilled spirits in 1990. 

Procedure Into a standard distillation apparatus, alcohol still, or other means, place 1250 milliliters (42.2 fluid oz.) of vodka, and then distill the alcohol at 80 Celsius for about 4 hours. After 4 hours, remove the heat source, and then recover the alcohol that distilled over into the receiver flask or receiver container. Now, place this alcohol (which will be composed of about 90%+ ethyl alcohol), into a large seperatory funnel or equivalent, and then add in 50 grams (3.5 oz.) of pickling salt. Thereafter, vigorously shake the entire mixture for about 10 minutes. After 10 minutes, allow the mixture in your seperatory funnel or equivalent, to stand for about 30 minutes. Thereafter, drain-off the bottom water layer and excess salt, and thereafter, recover the upper alcohol layer. Now, place this recovered upper alcohol layer into a standard distillation apparatus, as illustrated in method 1 or similar, and then add in 500 milliliters (17 fluid oz.) of fresh battery acid. Thereafter, boil this mixture at 100 Celsius for about 6 to 8 hours, and allow the mixture to distill during this time. After 6 to 8 hours, remove the heat source, and then recover the diethyl ether from the receiver flask or receiver container. Then re-distill this diethyl ether using a standard fractional distillation apparatus or equivalent in the same manner as in method 1 (distill at 40 Celsius). Note the battery acid mixture left over, can be recycled, but it must be boiled to drive-off at least 1/3 of the total volume (to remove water). 

While the surface of the strips is still moist with vodka, he adds enough of a 2% by weight solution of mercury QI) chloride (aka mercuric chloride, HgCI2) in distilled water to completely cover the foil. He allows this to react for about 2 minutes, then pours off the mercury solution. He rinses off the strips with distilled water, then with 190 proof vodka, and finally with moist ether. Moist ether is either purchased as is, or made by adding water to anhydrous ether with stirring until a water layer begins to appear at the bottom of the ether. The chemist uses this material immediately after making it. 

This acetone which remains still contains a lot of PETN. The best way to get the PETN out of the acetone which remains is to drip 190 proof grain alcohol (vodka) or 91% isopropyl alcohol into the acetone with stirring. As alcohol is added to acetone, its ability to dissolve PETN decreases. This is because PETN doesn t dissolve well in alcohol, so adding it to the acetone makes the solution lousy at dissolving PETN. This method is much better than boiling away more acetone because that method leads to a final crop of crystals that are dirty. When the solution is about half alcohol, all the PETN should be out of solution in the form of crystals. This is filtered out, and the acetone-alcohol mix is then tested to see if all the PETN is out of it by adding some more alcohol to see if more crystals form. If they do, alcohol is added until no more crystals form. 

Well, it still contains up to 70% ethanol (which makes it nearly twice as strong as most vodkas or whiskeys), so it wouldn t take many shots to make most people s minds go weak. 

Why does making the still work harder decrease the water content of the vodka Why does increasing the flow of reflux from the 12-oz can back to the big can improve separation efficiency between alcohol and water ... 

Well, if I reduced the heat to the still a lot, and removed the No. 1 coil (so that its heat removal duty was zero), then vapor would just blow through the 12-oz can. The water content of the vapor from the big can would be the same as the water content of the vodka in the bottle. The 12-oz can would then serve no purpose. However, as I partially condense the vapor flow into the 12-oz can, the water content of the vapors flowing into the bottle goes down, because water is less volatile than alcohol. The extra heat added to the big can prevents the extra heat removed by the No. 1 coil from reducing vodka production. 

The fermented mash is distilled in traditional pot stills or stainless steel columns where heat or steam strips the alcohol from the fermented mash. The alcohol vapors are recondensed and redistilled up to nine times. The vodka distillation process removes the heads and tails rich in ethyl acetate and ethyl lactate as well as fusel alcohols, so the finished beverage mainly consists of pure ethanol with some water. Most distilleries obtain 95% ethanol after distillation and rectification and dilute the vodka to obtain liquor with 40% ethanol. There are some vodkas that contain as low as 37° alcohol and some that contain up to 70° alcohol. The water used to decrease the alcohol content is important and is generally obtained from wells, glaciers, lakes, or springs. The distillation process concentrates the alcohol. Some distilled alcohols are filtrated through charcoal obtained from the apple tree (Malus domestica) or abedul (Betula alba) wood. 

Distillation is a ubiquitous process, used for a huge variety of chemical separations. In the popular imagination, it is associated with the production of ethanol. Wine is distilled to make brandy beer is distilled to make whiskey and corn mash is distilled to make gin, vodka and other white spirits. Distillation originated in efforts to increase the alcohol concentration of wine, thus making the wine more stable to heat. Many cultures seem to have been involved the stills shown on the labels of Irish whiskey bottles are aliqui-taras, a form of Spanish still based on designs by the Moors, who are believed to have gotten their ideas from the Chinese. 

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