Vanadium in the arts.

Manufacturer and builder 5, 1882

Some years ago it was discovered that the salts of this metal were admirably adapted for the production of aniline blacks, and for many other operations of printing and dyeing. The objection to their use, however, resided in their high cost, in consequence of the rarity of the metal. Nevertheless, some of the French calico printers, more than fifteen years ago when vanadium compounds with 50 per cent of the metal were sold at nearly the price of gold, found it economical to employ them, because of their wonderful efficiency. The salt usually employed was the meta-vanadate of ammonium.

The growing demand for vanadium salts in the above mentioned branches of industry, caused the gradual cheapening of the price of its salts, by calling into play the ingenuity of chemists in improving the methods of their production, and in seeking for other and cheaper sources of supply.

Walz and others, some years ago, showed that vanadium was an almost constant accompaniment of iron ores; and it now appears that the compounds of thin metal may be cheaply obtained from lice slags which accumulate in quantity at all large iron works. In this way, aniline blacks have been praluced for some years, at one of the leading French establishments, from certain slags of the Creusot works, and with the most satisfactory results.

About the beginning of the present year, the announcement was made in France that great quantities of vanadium had been observed to exist in the silicates of the alkaline earths remaining from the manufacture of steel by the Thomas and Gilchrist process. The phosphoretted cast iron contains vanadium, which is oxidized on blowing in air, and remains in the slag. The slags contain, on an average, 1 per cent of metallic vanadium, and by selecting the slags. 2 par cent may be obtained. On treating the slags with muriatic acid, a solution of a vanadium salt is obtained, which, in spite of the presence of impurities may be used at once for printing. With 200 parts of muriatic acid at 32° Tw., 100 parts of ground and sifted slags may be perfectly extracted. The powder is stirred up in twice its weight of water, and the acid is added gradually, stirring constantly; a little adphuretted hydrogen escapes, and the silica separates out as soon as a temperature of 158° Fah. is reached. Then 600 parts are added. The solution is allowed to stand, filtered, and left to deposit a little more silica. The extract of 2 ounces of ground slag is said to be sufficient for 1.750 pints of color.

From the above, it appears that no far from being a rare substance, vanadium is comparatively common. When one considers the enormous masses of slag formal in the extensive operations of steel making, the fact that they contain as much as 1 per cent of vanadium, means that many tone of the metal could he profitably extracted from this source should there be a demand for such large quantities. We have here again confirmed, the fact that experience respecting supposedly rare substances is uniformly the game. The substance is rare so long as there are no uses for it; but so soon as it is found to possess useful or valuable properties; we are astonished to find how common it is. It is not much more than twenty years ago since paraffin was a chemical curiosity not to be found outside of the laboratory, and glycerine wax unknown in the arts.

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