Urine, phosphorus extraction from

Of all the elements, phosphorus is the only one that was first isolated from a human source. The element was extracted from human urine in 1669 using an unsavory process After a sample of urine was allowed to stand for several days, the putrefied liquid was boiled until only a paste remained. Further heating of the paste at high temperature produced a gas that condensed to a waxy white solid when the vapor was bubbled into water. It wasn t until 1779 that phosphorus was discovered in mineral form, as a component of phosphate minerals. 

Sason To avoid boredom, I usually tell the students/readers about the significance of the molecules we make, something about history, and sometimes funny stories (e.g., the discovery of phosphorus by Hennig Brand by extraction from urine). 

Trichloroethanoic acid, CCI3COOH. A crystalline solid which rapidly absorbs water vapour m.p. 58°C, b.p. 196-5" C. Manufactured by the action of chlorine on ethanoic acid at 160°C in the presence of red phosphorus, sulphur or iodine. It is decomposed into chloroform and carbon dioxide by boiling water. It is a much stronger acid than either the mono- or the dichloro-acids and has been used to extract alkaloids and ascorbic acid from plant and animal tissues. It is a precipitant for proteins and may be used to test for the presence of albumin in urine. The sodium salt is used as a selective weedkiller. 

Phosphorus (P, [Ne]3.v23// ), symbol and name from the Greek word Ojj s(jopoe (bringer of light). Discovered (1669) by the German alchimist Hennig Brand, who extracted phosphorus from urine. 

After the discovery of phosphoric acid in the hones of the vertabrata, the old methods of extracting phosphorus from urine were totally abandoned, and it is now obtained almost exclusively from bones, Phosphoric acid exists In bones In the annexed form —... 

Phosphorus was first isolated in the seventeenth century by a procedure, which gave a recovery of about one ounce of phosphorus from a hogshead (large barrel, ca. 238 L) of urine [8]. In 1769, a more convenient method that made larger quantities accessible was developed by Scheele. This involved treating crushed bones with sulfuric acid and extraction of the phosphoric acid from the gypsum with small amounts of water. The water was then evaporated and the residual phosphoric acid mixed with charcoal, and then vigorously heated (Eqs. 10.2 and 10.3). 

As I mentioned already, the red form of phosphorus can be used for production of matches and gunpowder. As a result, producing phosphorus garnered a lot of interest by states and by private industry. For years, enlisted soldiers in Europe had to give urine as part of their service. You can imagine the stench of these phosphorus products The scientist who ridded the world from this stench was the great Swedish chemist Carl Wilhelm Scheele, who developed a method to extract phosphorus from bone ashes and plants. Sweden became a major exporter of matches in the nineteenth century. 

A few elements, such as copper, have been known for thousands of years. But most were discovered in the last 400 years. This shows Henry Brand, the German alchemist, on his discovery of phosphorus in 1659. He extracted it from urine, by accident, during his search for the elixir of life. To his amazement it glowed in the dark. 

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