About Me

When not at work with students, I spend my time in my room either reading, calculating something using pen and paper, or using a computer. I read almost anything: from the pornographic to the profound, although my main interests are mathematics and physics. "When I get a little money I buy books; and if any is left I buy food and clothes." -Erasmus

Tuesday, March 29, 2011

Ethanol and physics for future presidents

I spent last night reading Physics for Future Presidents by Richard Muller. It's a physics book intended for a general audience (not much in the way of mathematics-- only arithmetic!). The most timely issues (post Fukushima) discussed are radioactivity and nuclear power plants, but it also talks about terrorism, alternative energy sources and global warming.

The funniest thing I learned though is the radioactivity requirement that drinkable alcohol (wine, spirits, etc) must satisfy, at least in the United States. Drinkable alcohol, as mandated by law, should be radioactive. If the activity falls below a mandated threshold, the alcohol is considered unfit for human consumption. In  Muller's own words:

"Alcohol is radioactive too-- at least the kind we drink .... In fact, the US Bureau of Alcohol, Tobacco, Firearms and Explosives tests wine, gin, whiskey, and vodka for radioactivity. A fifth of whiskey must emit at least 400 beta rays every minute or the drink is considered unfit for human consumption." 

The reason? Since ethyl alcohol can be produced from crude oil, the only way we can differentiate the two is via radioactivity. The ethyl from fruits and other fermented products contain radioactive Carbon 14 absorbed from the atmosphere. Crude oil, although also from plants and animals that absorbed radioactive Carbon 14 , differs from recently dead plant matter (from which we get the raw materials for fermentation) in that radioactive carbon in crude oil has decayed long ago.

Now ethyl alcohol, no matter how it's produced, is chemically identical. This means it doesn't matter what you drink: the effects will still be the same. The reason such a law was made is economic. If the process that extracts ethanol from crude oil becomes cheaper than fermentation, then it would make sense to drink ethanol produced from crude oil. The law exists to make this alternative illegal, thus protecting vineyards and other industries that use fermentation from competition.

I still don't know which process is more expensive, even after a Google search. While on the hunt, I did learn about why we have denatured alcohol: the law and taxes. Denatured alcohol is ethanol  mixed with other agents (poisons, emetics, bittering agents) to make it undrinkable. Aside from drinking, ethanol has other uses: antiseptics, cleaning agents, etc. Although pure ethanol would be preferred, it would be too expensive since it is heavily taxed. To lower the price, ethanol is mixed with additives to make it undrinkable, hence exempt from the higher tax rates.

As I've said, Muller does talk about other things. The discussion of radioactivity, bombs and power plants is excellent. Someone who has read the book would not have been susceptible to the stupid claims about radioactive materials reaching the Philippines and the ensuing panic. Alas, his book is expensive here in the Philippines, and I suspect, doesn't sell well. I had to borrow my thesis adviser's copy because I couldn't afford to buy it from local bookstores. But if you can get your own copy...

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