Part 310

«Silver Nitrate Test for Cottonseed Oil.»—Investigations of Charabout and March throw some light on the value of this test in presence of olive oil. The free-fat acids obtained from cottonseed oil by saponification were treated in accordance with the method of Milliau on a water bath with a 3 per cent solution of silver nitrate, and the brown precipitate thus formed subjected to a chemical examination. It was found to consist chiefly of a brown silver salt composed of a fat acid melting at 52° F., and {483} congealing at 120° to 122° F., and of sulphide of silver. Olive oil, which contains a sulphur compound of an analogous composition, is also capable of forming a more or less distinct precipitate of a dark colored silver sulphide with nitrate of silver. It is important to bear this fact in mind when examining olive oil for cottonseed oil.

«Floral Hair Oil.»—

White vaseline 5,000 parts Floricin, pure 800 parts Linalool rosé 60 parts Terpineol 50 parts Aubepine (hawthorne), liquid 12 parts

«Floral Hair Pomade.»—

White ceresine 250 parts Floricin, pure 1,600 parts Vanillin 3 parts Geranium oil 5 parts Isoeugenol 4 parts

«Floricin Brilliantine.»—

Floricin oil 2,100 parts White ceresine 250 parts Ylang-ylang oil 2 parts Kananga oil 5 parts Oil of rose, artificial 1 part Cheirantia 5 parts

«Solid Linseed Oil.»—Cements for the manufacture of linoleum and other similar substances are composed to a large extent of linseed oil, oxidized or polymerized until it has become solid. The old process of preparing this solid oil is tedious, costly, and invites danger from fire. It consists in running linseed oil over sheets of thin cloth hung from the top of a high building. The thin layer of oil upon the cloth dries, and then a second layer is obtained in the same way. This is continued until a thick skin of solid oil is formed on either side of the cloth. A new method of solidifying linseed oil is by means of alkalies. The drying oils, when heated with basic substances such as the alkalies, polymerize and become solid. Hertkorn makes use of the oxides of the alkaline earths, or their salts with weak acids, such as their soaps. When chalk or lime is added to the oil during the process of oxidation, either during the liquid or the plastic stage, it forms a calcium soap, and causes polymerization to set in in the partially oxidized oil. Similarly, if caustic soda or caustic potash be added, the action is not caused by them in the free state, but by the soaps which they form. Oxidized oil is more readily saponified than raw oil, and the greater the oxidation, the more readily does saponification take place. Lime soaps are not soluble in water, whereas soda and potash soaps are. Consequently a cement made with the latter, if exposed to the weather, will be acted upon by rain and moisture, owing to the soluble soap contained in it, while a cement made with lime will not be acted upon. It is suggested that the action of the bases on linseed oil is simply due to their neutralization of the free acid. The acidity of linseed oil increases as it becomes oxidized. When the basic matter is added part of the free acid is neutralized, and polymerization sets in. The presence of a large amount of free acid must therefore hinder polymerization. From 5 to 10 per cent of chalk or lime is considered to be the amount which gives the best result in practice.

«Decolorizing or Bleaching Linseed Oil.»—Linseed oil may be bleached by the aid of chemical bodies, the process of oxidizing or bleaching being best performed by means of peroxide of hydrogen. For this purpose, the linseed oil to be bleached is mixed with 5 per cent peroxide of hydrogen in a tin or glass bottle, and the mixture is shaken repeatedly. After a few days have elapsed the linseed oil is entirely bleached and clarified, so that it can be poured off from the peroxide of hydrogen, which has been reduced to oxide of hydrogen, i. e., water, by the process of oxidation. The use of another oxidizing medium, such as chloride of lime and hydrochloric acid or bichromate of calcium and sulphuric acid, etc., cannot be recommended to the layman, as the operation requires more care and is not without danger. If there is no hurry about the preparation of bleached linseed oil, sun bleaching seems to be the most recommendable method. For this only a glass bottle is required, or, better still, a flat glass dish, of any shape, which can be covered with a protruding piece of glass. For the admission of air, lay some sticks of wood over the dish and the glass on top. The thinner the layer of linseed oil, the quicker will be the oxidation process. It is, of course, necessary to place the vessel in such a manner that it is exposed to the rays of the sun for many hours daily.

«Linseed Oil for Varnish-Making.»—Heat in a copper vessel 50 gallons Baltic oil to 280° F., add 2 1⁠/⁠2 pounds calcined white vitriol, and stir well together. Keep the oil at the above temperature for half an hour, then draw the fire, and in 24 hours decant the clear oil. It should stand for at least 4 weeks. {484}

«Refining Linseed Oil.»—Put 236 gallons of oil into a copper boiler, pour in 6 pounds of oil of vitriol, and stir them together for 3 hours, then add 6 pounds fuller’s earth well mixed with 14 pounds hot lime, and stir for 3 hours. The oil must be put in a copper vessel with an equal quantity of water. Now boil for 3 hours, then extinguish the fire. When cold draw off the water. Let the mixture settle for a few weeks.

«MINERAL OIL:»

See also Petroleum.

«Production of Consistent Mineral Oils.»—

By weight

I.—Mineral oil 100 parts Linseed oil 25 parts Ground nut oil 25 parts Lime 10 parts

II.—Mineral oil 100 parts Rosin oil 100 parts Rape seed oil 50 parts Linseed oil 75 parts Lime 25 parts

«Mixing Castor Oil with Mineral Oils.»—Castor oil is heated for 6 hours in an autoclave at a temperature of 500° to 575° F., and under a pressure of 4 to 6 atmospheres. When cold the resulting product mixes in all proportions with mineral oils.

«BLEACHING OILS:»

«Linseed Oil or Poppy Oil.»—Agitate in a glass balloon 25,000 parts, by weight, of oil with a solution of 50 parts, by weight, potassium permanganate in 1,250 parts, by volume, of water. Let stand for 24 hours at a gentle warmth and add 75 parts, by weight, of powdered sodium sulphite. Agitate strongly and add 100 parts, by weight, of hydrochloric acid and again agitate. Let stand until decolorization takes place, then wash the oil with a sufficiency of water, carrying in suspension chalk, finely powdered, until the liquid no longer has an acid reaction. Finally filter off over anhydrous sodium sulphate.

«Boiled Oil.»—The following is especially adapted for zinc painting, but will also answer for any paint: Mix 1 part binoxide of manganese, in coarse powder, but not dusty, with 10 parts nut or linseed oil. Keep it gently heated and frequently stirred for about 30 hours, or until the oil begins to turn reddish.

«British Oil.»—

I.—Oil of turpentine 40 parts Barbadoes pitch 26 parts Oil of rosemary 1 part Oil of origanum 1 part

II.—Oil of turpentine 2 parts Rape oil 20 parts Spirit of tar 2 parts Alkanet root, quantity sufficient.

Macerate the alkanet root in the rape oil until the latter is colored deep red; then strain off and add the other ingredients.

«Decolorizing and Deodorizing Oils.»—I.—One may partially or completely deodorize and decolorize rank fish and other oils by sending a current of hot air or of steam through them, after having heated them from 175° to 200° F. To decolorize palm oil pass through it a current of steam under pressure corresponding to a temperature of 230° F., agitating the oil constantly. The vapor is then passed through leaden tuyeres of about 2 inches diameter, 10 hours being sufficient for deodorizing 4 tons of oil.

II.—Another method that may be applied to almost all kinds of fats and oils with excellent results is the following: Melt say 112 parts, by weight, of palm oil in a boiler. When the mass is entirely liquefied add to it a solution of calcium chloride, made by dissolving 7 parts, by weight, of lime chloride for every 84 parts, by weight, of oil in water, and mix intimately. After cooling, the mass hardens and is cut into small bits and exposed to the air for a few weeks. After this exposure the material is reassembled in a boiler of iron, jacketed on the inside with lead; a quantity of sulphuric acid diluted to 5 per cent, equal in amount to the lime chloride previously used, is added, and heat is applied until the oil melts and separates from the other substances. It is then left to cool off and solidify.

«Decomposition of Oils, Fats, etc.»—In many of the processes at present in use, whereby oils and fats are decomposed by steam at a high pressure, the time during which the oil or fat has to be exposed to high pressure and temperature has the effect of considerably darkening the resulting product. Hannig’s process claims to shorten the time required, by bringing the steam and oil into more intimate contact. The oil to be treated is projected in fine streams into the chamber containing steam at 8 to 10 atmospheres pressure. The streams of oil are projected with sufficient force to cause them to strike against the walls of the chamber, and they are thus broken up into minute globules which mix intimately with the steam. In this way the most satisfactory conditions for the decomposition of the oil are obtained. {485}