Acetylene Purification.

Progress, Volume I, Issue 5, 1 March 1906, Page 116

Acetylene Purification.

P. Gril proposes in his French patent, 3341 11 of 1903, to extract from crude acetylene made from calcium carbide, the organic compounds of sulphur, the basic compounds ormed by polymerisation, and the phosphine which it usually contains. For this purpose ten parts of chromic acid are dissolved in thirty parts of nitric acid, and the solution is absorbed in 100 parts of kieselguhr. Messrs. L. M. Bullier and L. Maquenne, who have investigated the origin of the impurities usually, present in crude acetylene made from calcium carbide, state that the compounds of phosphorus come from the

calcium phosphide in the latter material. They find that this phosphide, and the analogous calcium sulphide, only occur in carbide when it is made by the usual " basic " process — i.e., when the charge fed into the electric furnace contains lime in excess. If the carbide were prepared with carbon in excess it would not be so contaminated. The white haze which is produced when C2H2 containing PH3 (phosphme) is burnt in a closed room, consists of ammonium phosphate. Ammonia is of itself an objectionable gas, and if it enters into a purifier containing material mtended to extract phosphorus, it reacts with that material and lowers its efficiency. The source of the sulphur is not yet traced. The SH2 was formerly said to come from calcium monosulphide, or from aluminium sulphide ; but it appears more likely that it is formed when a triple compound of carbon, sulphur, and calcium comes in contact with water. A troublesome mechanical impurity is lime dust from the gas generator, which is difficult to remove even by a water washer, and is visible in the luminous acetylene flame if the gas has been passed through tubes containing wool moistened with HCI or H2SO4. The lime dust deposits at the burner orifices and gradually decreases their effective diameter. Luigi Mascarelli has examined the " explosive compound " formed, amongst other substances, on slowly passing acetylene through nitric acid of specific gravity 1.52, and finds it to have the composition C4H207N6. "When heated with caustic potash this substance gives off ammonia, and on being heated with light petroleum it also suffers decomposition.

The Financial News has unearthed a proposition which should render the financial future of shipping enterprises magnificent in the extreme. It appears that a Victorian genius suggests coating the bottom of steamers with quicksilver, thereby forming a magnificent amalgamating plate, to gather the gold as the boat travelled. On arrival at the port of destination the cargo is discharged and the ship goes into dock for a clean-up. The author of this brilliant idea has, our contemporary states, expressed his desire to accept the position of battery manager and amalgamator. But he is not at all up-to-date. He should issue a circular and become his own ship-owner, and then secure a dry dock, thus keeping the wealth " in the family."