Extracting 99% of the ethanol in a wash скачать в хорошем качестве

Extracting 99% of the ethanol in a wash

There is a sort of hard limit on how much ethanol you can get from a fermentation. The first is how much alcohol can be made from all the sugar and have the yeast survive. That is about 20% but as much as 30% under perfect conditions. More often it is less. When an ethanol wash is distilled are can extract most of the ethanol. That can turn 20 litres of wash into 4 litres of 95% ethanol. The key is here is that 95% figure. You can not extract the last 5% via normal distillation methods. It leaves a small amount behind. The reason for this is that ethanol and water is an azeotropic mixture. Azeotropes become harder to separate at a particular point. At 5% ethanol and 95% water water and ethanol boil at the same temperature. This is about 78 degrees Celsius. Not nought o remove ethanol alone or water alone. This is a result of the way ethanol and water , and other azeotropes, interact at a chemical level. As it is a chemistry problem chemists have also found ways to remove that last 5%. There are a range of ways to handle azeotropes. There 3 methods described in this video are: Azeotropic distillation Pressure-swing distillation Chemical action separation These 3 methods use different mechanisms to take advantage of the chemistry of azeotropes. Sometimes it is by adding extra chemicals, sometimes it is is a matter of extra equipment. You can even use a combination of the two. One or more of these can remove that last 5% of ethanol. In fact they are useful for many different chemicals. Removing nearly all, if not all, water from a chemical can be very important. Anhydrous, or without any water, chemicals are important for research and pharmaceuticals. The removal of water is essential for keeping reactions predictable and minimises unwanted products. While ethanol may only be a simple example the underlying principles are the same.