Tuesday, September 27, 2011

Why Pee is Cool - entry #4 - "PeePee Portal to Phosphorus" or "What the Alchemists Did Right"

Travel with me back in time, when humans were first beginning to wonder things like "What the hell is the world around me made of anyhow!?"  Picture yourself as an ancient alchemist, repeatedly trying in vain to figure out a way to turn anything into gold.  You pretty much suck at doing science, but as a result of all your fool-hearty work you do know how to do things like mix, heat, and distill stuff.  The first problem you face as an alchemist is that you need some substance to do experiments on.


It turns out that a pissload of alchemists spent centuries doing crazy experiments on PEE!  They boiled it, they added stuff to it, they let it rot, they distilled it, etc.  Finally, in 1669 one dude used pee to discover one of the most poisonous substances then known, a new glow-in-the-dark element he called phosphorus.  Here is a dramatized picture of the alchemist/chemist/scientist (the distinction has never really been clear to me) Hennig Brand, attempting to discover the philosopher's stone, but actually discovering the chemical element phosphorus.  What a good day in the lab!!!

The Alchemist in Search of the Philosophers Stone by Joseph Wright.  Depiction is of Hennig Brand discovering the element phosphorus.  The glow of phosphorus shown is 4sure exaggerated.

Nobody knew what a chemical element was at the time, but phosphorus turned out to be the 13th one ever discovered.  Since then we have discovered 105 more!  Phosphorus caused quite a stir upon its discovery in part because it glows (!!!), which I'm sure blew everyone's post-medieval mind!  The light-producing mechanism is just like that from glow-sticks, and is known as chemiluminescence (not phosphorescence...confusing, huh?).  In the case of phosphorus, it glows when it comes into contact with oxygen.  It spontaneously combusts!

Phosphorus' love affair with oxygen explains why it primarily occurs in nature combined with four oxygen atoms, in a species known as a phosphate ion (PO43-), which is pictured below.  The negative charges on the oxygen atoms are balanced in our urine by positively charged ions like protons, sodium and ammonium to make things like disodium hydrogen phosphate (Na2HPO4).

The Phosphate Ion (not actual size).

Though we need phosphates in our bodies (for bones, DNA, and cellular communication), we pee them out simply because any atoms that enter our bodies (via eggs, milk, beans, etc) eventually have to leave (via pee, duh).

Why are we talking about phosphate ions in pee?  Because it was the PeePee Phosphate ions that Brand turned into phosphorus.

Though Brand kept his recipe hidden for as long as he could, we now know that it required 121 gallons of urine (imagine 121 pee-filled milk jugs!!) to produce a single gram of phosphorus (1 small paper clip = 1 gram).  So inefficient, but still a pretty good start!  Brand's recipe was inefficient because it called for a number of steps we now know are unnecessary and/or wasteful.  One of these steps called for letting the urine "lie steeping in one or more tubs til it putrify and breed worms".  Worms!!!!

I will skip the details of Brand's insane method and summarize the simplified method that was developed by those who came after him.  First, you gather all 121 gallons of urine and boil away all the water, leaving behind a thick syrup.  You then combine that syrup with some sand in an old-school container known as a retort.  At the end of the retort is usually some sort of collection flask, like the one you see glowing in the above painting and also in the scheme below.

Contraption to turn pee into phosphorus.  Fully-assembled apparatuses like this are known as alembics, and are classic alchemical tools.

You then heat the crap out of the syrup/sand mixture, which performs two important reactions.  The first is to turn the organic molecules in the pee syrup (amino acids, creatine, etc) into charcoal, which is basically pure carbon.  This is just like burning a marshmallow on a campfire, and it happens in this case because of the high heat and low oxygen content inside the retort.  In the second reaction the newly-formed carbon atoms steal the oxygen atoms from the phosphate ions, in turn forming elemental phosphorus!  Other stuff happens with the sodium ions and sand, in an overall reaction that looks something like this.

Shout out to the chemists in the audience who spent more than 0.25 seconds on this graphic! :-)

Amazingly, this is essentially the same process used to produce phosphorus today, except calcium phosphate ore is used in place of pee and the carbon comes from coke instead of decomposed pee molecules.

Phosphorus then went on to have quite an impact on human history.  Its toxicity and spontaneous-combustion properties led to its widespread use in weapons during World War I and later wars.  Those same spontaneous-combustion properties also allowed phosphorus to revolutionize the match-making industry.  Unfortunately, at the time of its discovery, phosphorus was the most toxic substance ever synthesized by humans.  This meant that countless people in the public and especially the match-making industry died or were injured due to phosphorus exposure. Phosphorus exposure causes a horrible disease known as "phossy jaw" in which the afflicted person's jaw rots away.  If the jaw is not removed quickly this condition leads eventually to death from organ failure.  DARK!  Chemicals can be dangerous, so we should all be careful when we create new ones!

Mega phossy jaw, housed in London's Hunterian Museum.  via  londonist.

As more and more people died from phosphorus matches, match makers went on strike and countries started banning them.  New matches were invented that used the less toxic form of phosphorus known as red phosphorus.  We have been talking about white phosphorus up until now.  The only difference between the two is that the atoms are arranged in a different way, which among other things causes red phosphorus to be way less toxic than white phosphorus.  Match technology marched on, read more here.

SUMMARY of INSANITY!!!:  Alchemists, though they have a bad reputation now (undeservedly, imho), are responsible for the discovery of the element phosphorus through their weird experiments with pee.  The way they figured out to make it is essentially the same way we make phosphorus today, and the manufacture of phosphorus went on to revolutionize the way we fought wars and started fires.  All because of curiosity and pee!!!

Further reading: The 13th Element: The Sordid Tale of Murder, Fire, and Phosphorus by John Emsley

Related Posts:
PeePeePost #1: "Why Is Pee Yellow?" or "Rainbow of Urine"
PeePeePost #2: "Why Does Pee Smell?" or "Aroma of Life"
PeePeePost #3: "Explosive Urination" or "Gunpowder Comes from Pee!!!"
PeePeePost #5: "How Pee United You With Rocks"
PeePeePost #6: "Pee, Our Connection with the Earth's Metabolic Cycle"