June, 1912 T H E JOL-RAYa4L OF I.\-D CSTRIAL A N D E,VGIi\-EERISG C H E X I S T R Y . 4 4 3

degree from 0.1-1 per cent., and so on to the sixth degree. It is stated that as technical products of the fourth degree and upwards (less than 0.01 per cent. impurity), the following metals may be obtained: cadmium, copper, gold, lead, mercury, plati- num, silver and zinc. Zinc, cadmium and tin (Kahlbaum) have all risen from the third to the fourth degree since 1895. Redis- tilled zinc was found to contain from 0.007-0.0088 per cent. total impurity, whereas a sample of electrolytic zinc costing ten times as much contained 1.3 per cent. of zinc sulphate, about 6 per cent. of zinc hydroxide, 0.02 per cent. of insoluble silicate, and 0.04 per cent. of metallic impurity.

T H E COST O F CHLORINE. The following costs per ton of active chloridc are compiled

from a recent paper by Kershaiv (Chem. Trade J . , 50, 330, 385) : Method of Form of

preparation. combination. Cost. Remarks. Chemical. Calcium hypo- $68.82 Taking3 tons 3.5%; bleach

chlorite. and assuming 5% loss

Chemical. Sodium hypo- 98.62 Using sodium sulphate to chlorite. decompose calcium hy-

Chemical. Sodium hypo- $109.96 Using sodium carbonate, chlorite. ibid.

Electrolytic.’ Sodium hypo- $106.33 6.07 kw. hrs. and 6.0 kg. chlorite. salt per kg. chlorine: 15

kg. C1 per 10-hour day. Electrolytic. Sodium hypo- $1 12.13 Power a t $0.008 per kw.

Electrolytic Sodium and mag- $392.28 Actual cost a t Poplar, Eng- (“Hermite” nesium hypo- land, where 50,726 gal. electrolyzer). chlorite. of hypochlorite solution

of chlorine.

pochlorite.

chlorite. hr.

were produced (1910).

SYNTHETIC ORGANIC DYES AND PATENTS F O R T H E MANUFACTURE OF T H E SAME, 1907-’11.

(Lehmann, C k m . Ind., 35, No. 7, 207.) 1907. 1908. 1909. 1910. 1911.

,---- ---.- 7---- ----- -_-.-

Groups. Nitro. . . . . . . . . . . . . . . . Azo, substantive.. . . . . Azo. acid. . . . . . . . . . . . . Azo, chrome., . . . . . . . . Azo, basic. . . . . . . . . . . . Azo, varnish.. ........ Azo, “ingrain”. . . . . . . . Triphenylmethane.. , . . Pyronine. . . . . . . . . . . . . Acridine. . . . . . . . . . . . . Wtroso . . . . . . . . . . . . . . Anthracene, . . . . . . . . . . Indophenols. . . . . . . . . . Oxazine. . . . . . . . . . . . . . Thiazine. . . . . . . . . . . . . Azine. . . . . . . . . . . . . . . . Quinoline. , . . , . , . . , , . Indigo, Thioindigo. . . . Sulphur. . . . . . . . . . . . . . Constitution, unknown

. . . . . . . . . . . . . . 1 . . 1 54 5 123 14 85 23 92 13 72 19 35 11 38 11 37 6 58 27 50 18 3 7 20 52 8 38 10 44 19 37 7

1 2 . . . . . . . . . . 1 . . 1 5 6 19 9 11 11 13 15 8 5 2 1 1 3 4 2 5 3 7 1 i 8 5 7 5 3 9 1 1 1 0 9 1 4 4 . . 2 2 4 1 . . . . 3 1 1 . . . . . . . . . . . . . 1 1 1 . . . . . . 2 2 . . . I l l

16 32 13 40 30 54 13 50 24 93 . . 3 . . . . . . . . . . . . . . 3 . . 6 6 1 3 4 8 2 6 4 5 . . 2 . . . . . . . 1 . . . . . . . . 7 2 1 . . 4 1 . . 5 3 . . . . 2 1 . . . . 1 . . . . . . 4 28 15 59 15 45 21 4 7 8 90

3 7 16 64 24 40 12 45 21 22 i 2 3 1 1 . . 2 . . 2 . . 3

THE MANUFACTURE OF ALUMINUM FOIL. Aluminum foil is now being manufactured a t La Praz and

Charleville-sur-Xndelle by a French company, and a t Ludwig- To produce one ton of active chlorine per day, with the cheapest of

the electrolytic cells described by Kershaw, would require 50 electrolyzers and involve a capitalloutlay of about $37,500, while the more efficient and expensive types, wherein platinum-iridium electrodes are used, would cost double this amount.

shafen a. Rh. by a German concern. The German product, termed “Alolit-foil,” is being marketed as a substitute for tin- foil, and is said to be “from pure aluminum, and to be lead-free and non-poisonous.”

Guillet [Rev. Met., 9, 147 (1912)] has given an account of the processes conducted in France for the manufacture of aluminum foil. The metal, delivered to the works in the form of ingots, 700 X 320 X 1 2 0 mm. (cast a t 750O-775’ C.), is first hot-rolled a t 420’ C. to a thickness of 3.5 mm. and then cut into strips 8 cm. wide, which, after being annealed a t 420’ C., are cold- rolled to 0.04 mm. in six stages, further reduction in thickness being then effected by continued rolling or by hammering. In the former case the metal bands are first greased, then rolled in pairs to 0 . 0 2 mm. and subsequently in fours to the desired thickness of 0.01 mm., the foil thus being had in lengths of about 16 m In the latter case the bands are made into packets of 500 each and beaten by pneumatic hammers, each packet being placed between two thin sheets of zinc; when the thickness of the metal reaches 0.03 mm., the packets are hammered in pairs to 0 .02 mm., and finally in fours to 0.01 mm. The waste in either case is considerable, only about 33-35 per cent. of the 0.04 mm. metal employed being obtained as good foil I sq. m. of Ivhich weighs about 27 grams. The waste foil is employed for the production of aluminum powder. Prior to trimming and cutting to size, the sheets of foil are mechanically separated. In the manufacture of aluminum powder, the comminution of the waste foil is conducted in stamp mills in which the closed mortar-box is provided with a circle of 12 stamps actuated from a central shaft.

SOME N E W i‘NON-CORROSIVE” ALLOYS. The American market now affords a grade of sheet steel

known as “Vismcra,” possessing the following composition: Iron, 99.542 per cent.; copper, 0.200; manganese, 0.190; carbon, 0.036; phosphorus, 0.004; sulphur, 0.018; oxygen, 0.009; and hydrogen, 0.001. Particular attention is called to the copper and manganese content, and to the low percentage of oxygen. It has been known for some time that the presence of a small amount of copper increases the resistance of steel to corrosion, and that cupreous steel is more resistant to acid mine waters than ordinary steel. It is said that another producer has suc- ceeded in obtaining “an alloy steel that will successfully with- stand tests with sulphuric acid, the chief enemy of tubing and sheets . ”

Gaston Jacquier, of Belgravia, Transvaal, has patented an anti-corrosive alloy said to be suitable for employment in the manufacture of tanks, piping, ropes, valves, pumps, etc. (U. S. Patent 1,019,963, 1912). It is made of the following metals: Aluminum, gz per cent.; bismuth, z per cent.: copper, j per cent.; and silicon, I per cent. The composition may also be as follows: Aluminum, 91 per cent.; bismuth, 2 per cent.; copper, 5 per cent.; and magnesium, 2 per cent.

KUPRONIZING. According to Erlgiweeuiug (93, No. 2411, 367), a London firm

mainly concerned with copper-plating wood applies the name “kupronizing” to the process it employs. In the plating of wooden hand-rails, the wooden core is first impregnated with a preservative material and then flashed with either plumbago or a metallic salt. The actual copper deposition is then carried out in a‘bath in the usual manner. It is the present practice to deposit a layer about of an inch thick. Iron window- frames and iron pump-rams are now kupronized, and the process gives a copper layer which adheres so that the pieces may be machined after the copper is in place.