P H O S P H O R U S Interesting Phosphorus Topics Including SMITHELL`S COLD FLAME HITTORF`S METALLIC ALLOTROPE PHOSPHINE -- WILL O` THE WISP ? PHOSPHORUS AGRICULTURE

The Preparation of Phosphine - note smoke-rings

Will O` the Wisp

The spontaneous combustion, or luminous oxidisation, of marsh-gases containing phosphoretted hydrogen. Will o` the wisp is an elusive natural phenomenon. It is an occasional flickering glow or dim flame, appearing over swamp or marsh-land.

Marsh-gas, or methane CH₃ is formed from rotting vegetation and bubbles up from submerged mud. The methane can have an admixture of phosphoretted hydrogen, depending upon the nature of the rotting organic matter (a dead fish in anaerobic mud would be ideal). Phosphoretted hydrogen is the gas phosphine, or trihydrogen phosphide PH₃, carrying the vapour of the liquid, hydrogen phosphide P₂H₄. It is the hydrogen phosphide vapour which renders the gaseous mixture capable of spontaneous combustion.

Ignited methane will-o`-the-wisps will appear yellowish. Many accounts of the phenomenon say the colour is bluish. This could be the ignition of hydrogen sulphide gas, which is also evolved from rotting organic matter. On a purely speculative note, it would be interesting to replace the phosphorus in Smithells cold flame experiment with liquid hydrogen phosphide (a deadly poison), using no heat. If the result is the same, then the flickering green-glow type will o` the wisps could be accounted for, by the luminous oxidisation of hydrogen phosphide vapour, carried into the atmosphere by methane (non-ignited) or carbon dioxide gas.

The Preparation of Phosphuretted Hydrogen

The Glow of Phosphorus When white phosphorus is exposed to the atmosphere it oxidises, with the evolution of white fumes and accompanied by a faint green glow. If a small piece of white phosphorus is heated in a flask with water, phosphorus vapour is evolved with the steam. If a liebig condenser is attached to the flask and observed in the dark, a phosphorescent ring can be seen at the point where the steam condenses. Smithells Cold Flame from page 609, Partingtons Inorganic Chemistry -- The glow of phosphorus is shown in the "cold flame" experiment, due to Smithells. A few pieces of phosphorus are placed in a dry receiver, which is then filled up with glass wool. The receiver is heated on a water bath, a stream of dry carbon dioxide being passed through. The phosphorus vapour carried along with the gas oxidises in the air, and a green flame appears at the top of the exit tube. This is so cool that a finger may be held in it, and it will not kindle the head of a match.

The glow of phosphorus was minutely studied by Boyle, who found that solutions in some essential oils (oil of cloves) showed the same character, whilst in others (oils of mace and aniseed) there was no phosphorescence. He also noticed a strong garlic-like odour, which we now know to be due to ozone. Frederick Slare noticed that the luminosity increased when the air was rarefied, an observation confirmed by Hawksbee and Homberg, and which was possibly the basis of Berzelius’s theory that the luminosity depended on the volatility of the element and not on the presence of oxygen. Lampadius, however, showed that there was no phosphorescence in a Torricellian vacuum; and other experimenters proved that oxygen was essential to the process. It depends on the partial pressure of the oxygen and also on temperature. In compressed air at ordinary temperature there is no glowing, but it may be brought about by heating. Again, in oxygen under ordinary conditions there is no phosphorescence, but if the gas be heated to 25° glowing occurs, as is also the case if the pressure be diminished or the gas diluted. It is also remarkable that many gases and vapours, e.g. Cl, Br, I, NH₃, NO₂, H₂S, SO₂, CS₂ inhibit the phosphorescence.

Allotropes & Psuedo-Allotropes

Schenk`s Scarlet Phosphorus. Phosphorus tribromide is prepared by gradually adding a solution of bromine in carbon disulphide to dry red phosphorus. The function of the carbon disulphide is to moderate the violence of the reaction. (If liquid bromine is dropped on red phosphorus in a cooled flask, the tribromide is formed with the evolution of light. White phosphorus explodes in contact with bromine.) The pure tribromide can then be fractionally distilled from the disulphide (CS₂ 46^o, PBr₃ 174^o) as an unpleasant mobile liquid. White or red phosphorus can now be dissolved in the tribromide to form a 10% solution. If this solution is boiled in a reflux still for about 10 hours, a fine scarlet amorphous powder is thrown down.

White or Yellow Phosphorus. A translucent white wax-like solid, stored under water because of its spontaneous combustion when exposed to the air. Below 5.5° it becomes brittle and the crystalline structure can be seen by etching a cooled stick of phosphorus in dil. nitric acid. Very soluble in carbon disulphide - 9 parts P to 1 part CS₂. Partington -
"On evapouration out of contact with air, the solution in carbon disulphide deposits crystals. Large transparent regular crystals, usually rhombdodecahedra which display a play of colours resembling that of diamond, are formed by the slow sublimation of phosphorus in an evacuated tube, one end being kept cool by a moist cloth. The tube is preserved in the dark, since on exposure to light the crystals become red and opaque."

Red Phosphorus. Used in the striking surface on safety match-boxes. Stable. Obtained by Schrotter in 1845 by heating white phosphorus for a few hours at 250° in a flask filled with nitrogen. The liquid deposits a red powder, and finally solidifies to a purplish-red mass. Can be prepared by the action of a silent or spark electrical discharge on the white allotrope.

Hittorf`s Metallic Phosphorus. In 1865 Hittorf heated red phosphorus in a sealed tube at 530<sup>o</sup>. The upper part of the tube was kept at 444<sup>o</sup> . Brilliant opaque monoclinic, or rhombohedral, crystals sublime. Can also be prepared by dissolving white phosphorus in molten lead in a sealed tube. 500° for 18 hours. Upon slow cooling, Hittorf`s allotrope crystallises out. The crystals can be revealed by dissolving the lead in dilute nitric acid followed by boiling in conc. hydrochloric acid.

Beta-Black Phosphorus. density 2.69, M.P. 587.5° fairly good conductor of electricity, formed irreversibly from white phosphorus at 200° under a pressure of 12,000 Kgcm^-1. If a trace of sodium is present under the same conditions, then Violet Phosphorus is formed, with a slightly lower density.

Brand Distills Urine in 1675 sells secret for thirty quid

Partington`s Text Book of Inorganic Chemistry 1946

Matches? Matches? I don` need no steeenking matches !

Match: a slip of wood or other combustible material, having its end covered with a composition which takes fire when rubbed either on any rough surface or on another specially prepared composition Godfrey Haukwitz in 1680, acting under the direction of Robert Boyle, who at that time had just discovered how to prepare phosphorus, employed small pieces of that element, ignited by friction, to light splints of wood dipped in sulphur. Experimental. In 1805 one Chancel, assistant to Professor L. J, Thénard of Paris, introduced an apparatus consisting of a small bottle containing asbestos, saturated with strong sulphuric acid with splints or matches coated with sulphur, and tipped with a mixture of chlorate of potash and sugar. The matches so prepared, when brought into contact with the sulphuric acid in the bottle, ignited, and thus, by chemical action, fire was produced

• The first really practical friction matches were made in England in 1827, by John Walker, a pharmacist of Stockton-on-Tees. These were known a “Congreves” after Sir William Congreve, the inventor of the Congreve rocket, and consisted of wooden splints or sticks of cardboard coated with sulphur and tipped with a mixture of sulphide of antimony, chlorate of potash and gum. With each box which was retailed at a shilling, there was supplied a folded piece of glass paper, the folds of which were to be tightly pressed together, while the match was drawn through between them.

• The so-called “ Prometheans,” patented by S. Jones of London ill 1830, consisted of a short roll of paper with a small quantity of a mixture of chlorate of potash and sugar at one end, a thin glass globule of strong sulphuric acid being attached at the same point. When the sulphuric acid was liberated by pinching the glass globule, it acted on the mixed chlorate and sugar, producing fire.

• 1833 phosphorus friction matches produced on a commercial scale by J. Preschel of Vienna & F. Moldenhauer in Darmstadt. The chief element in the igniting mixture of ordinary or “strike anywhere” matches used to be common yellow phosphorus, combined with one or more other bodies which readily part with oxygen under the influence of heat. Chief among these latter substances is chlorate of potash, others being red lead, nitrate of lead, bichromate of potash and peroxide of manganese. But the use of ordinary white or yellow phosphorus as a principal ingredient in the igniting mixture of matches was found to be accompanied with very serious disadvantages. It is a deadly poison, and its free dissemination led to many accidental deaths, and to numerous cases of wilful murder and suicide. Workers also who are exposed to phosphoric vapours are subject to a peculiarly distressing disease which attacks the jaw, and ultimately produces necrosis of the jaw-bone - phossy jaw.

• 1844 G. E., Pasch patents the safety match. Commercially produced by J. E. Lundstrom, of Jonkoping, Sweden, in 1852. Safety matches contain no phosphorus in the heads; they are tipped with, for example, chlorate of potash, 32 parts; bichromate of potash, 12; red lead, 32; sulphide of antimony, 24; while the ingredients of a suitable rubbing surface are eight parts of red phosphorus to nine of sulphide of antimony.

HYDROGEN PHOSPHIDES the deadly liquid and solid

FARMING FOR PHOSPHORUS Animal`s bones cater for Victorian phosphorus demand

The skeletal material of animals is first digested with a solvent such as benzene, carbon disulphide, ether or chloroform. Fatty organic matter is thus removed. The degreased bones are then digested with water in a pressure cooker. Gelatinous matters - glue - is thus removed. The degelatinised bones are then heated an iron retort, out of contact with the air. Liquid products such as bone oil distill over, and are thus removed. A residue of animal charcoal remains, which is then heated in the air to burn off any remaining organic matter. Bone-ash remains, which is impure calcium phosphate. Ca₃(PO₄)₂. This is then heated in an electric arc furnace with sand and coke, and phosphorus distills over.

An Autonomous Phosphorus Rendering Engine. In the mid eighteen-hundreds an attempt was made to fully automate phosphorus production. A self-powered (coal fired steam) autonomously mobile machine was designed to move about agricultural land, harvesting animals for the phosphorus in their bones.

An Autonomous Rendering & Mummification Phosphorus Harvester. circa.1860 drawn E.G. for pat.app.

Mummified meat, glue and Dippel`s bone oil were welcome by-products of the rendering & processing machine. An account in the February 20th 1861 issue of The Weardale Farming Gazette encourages interest in farming for phosphorus, then becomes more cautionary, as this excerpt illustrates--

"The problems of phosphorus farming are manifold and beset with danger. Ernest Glitch of Weardale has produced a steam powered mechanical bone stripper which can autonomously harvest phosphorus from any concentration of livestock. The deboned flesh is mummified during the phosphorus production.

During a recent Royal visit to the North of England, a demonstration of this machine went sadly wrong. The decimation of the Royal Entourage by the errant Rendering & Mummification machine left Queen Victoria in a state of apoplectic shock. Sixteen pounds of yellow phosphorus was harvested from the court officials, servants, hand-maiden and a Minor Royal. After the carnage, Mr. Glitch presented the phosphorus to Her Majesty, in an attempt to gain Royal patronage of his invention. The burns on Her Royal Highness` hands are said to be slowly de-ulcifying, and this writer hopes that phossy-jaw does not set in.

Her Majesties Government has indicated that present agricultural machinery is entirely sufficient for Britannia`s needs, phosphorus stocks presently show a surplus for match production and that demand for mummified meat remains low.

The War Department has, however, shown great interest - Mr. Glitch is presently modifying his rendering-engine for battle-field use."