 |
Home > the oil, another difficulty arose...
Previous Next The best candle and soap tips online! the oil, another difficulty arose in the large amount of objectionable color the crude oil contained, and which was due to dark resinous spots contained in the seed; the color, however, has been overcome, for it is now refined by means of chemicals, caustic lye, etc., and bleached with sulphuric acid, and pressed to remove the large amount of stearine it contains, and which, with the oils, is used for a great many purposes, this latter being sometimes sold and bottled as salad oil from its sweet nutty taste when fresh and pure. Cotton-seed oil, when well refined, is a bland, bright yellowish oil, very similar to almond oil, though it has some of the properties of a drying oil, but taking a very long time to dry. This drying property does not seem to deter the maker of cheap perfumery from bottling large quantities for common hair oil, or from buying it for that purpose under the name of olive oil, often not knowing from what source it is obtained. To the soap-maker it possesses very valuable properties, for nothing has yet been discovered that is so good and economical a substitute for olive oil; and when a portion of lard and bleached palm oil is mixed with it, for making Marseilles or Castile soap, it is difficult to distinguish the imitation from the genuine soap. The importance of this oil in the manufacture of soap is, to us, so great that we deem it necessary to devote some space to its description, to give soap manufacturers some hints for its manufacture into a soap that may be called Castile soap, from its close resemblance to it. In saponifying cotton-seed oil, there is no peculiar difficulty more than in making a good Castile soap from olive oil, though the soap is made somewhat sooner if the stearine is left in it, which stearine is general Impressed out to permit the oleine to remain fluid in the coldest weather. To make a white Castile soap, take:— Cotton-seed oil 80 pounds. Lard, good quality 10 " Olive oil 10 " 298 TECHNICAL TREATISE ON SOAP AND CANDLES. THE FABRICATION OF SOAPS. 293 And prepare the lye by close calculation in this manner: 50 pounds to mark 15° B., 50 pounds at 21° B., and 50 pounds at 27°, making 150 pounds for this quantity of grease—the lye to be made of the English caustic soda, and rendered clear and caustic with about one-fourth of lime. To the melted grease in the kettle pour the first 50 pounds of lye at 15°, keeping it stirred as the heat is raised to boiling, and as it froths beating it down quickly to prevent its overflowing; boil for three or four hours, when add by degrees the 50 pounds of lye at 21°, and boil for five or six hours longer, keeping up the stirring, and, when it becomes a perfectly smooth mass, turn off the heat and let it rest for the lye to separate. After some hours' rest the spent lye is drawn off, the heat is raised, and the last 50 pounds of lye at 27° are poured in, and allowed to boil briskly for four or five hours, when the soap ought to grain and appear flakey when pressed between the fingers; when again turn off the heat and allow the lye to separate, and draw off after some hours' rest. In finishing or fitting a lye of carbonate of potash of 6° or 8°, say 25 pounds are stirred in with a gentle heat until the soap presents a perfectly homogeneous syrupy mass, when it may be left to divide—the scum to the top and the gray soap to the bottom, with the fine soap between, which is dipped into the frames, and the scum and dark soap kept to make the mottled soap. The result should be about 150 pounds of the best soap having a fine white appearance, and 30 to 40 pounds of inferior soaps that can be mixed with the mottled Castile soup. To make a MOTTLED CASTILE SOAP FROM COTTON-SEED OIL. 80 pounds. 10 " 10 " Cotton-seed oil . Lard, good . Palm oil, bleached The bleached palm oil improves the odor, causing a greater resemblance to Marseilles soap, and is cheaper than the olive oil. Sulphuretted soda Iye3 are preferred by the French soap-makers for their mottled soap; but, as we are using the English soft lye or artificial lyes, we will have to adopt a modified process. The sulphuretted crude soda forms the colored mottling, the sulphur combines with the iron of the kettle and other impurities, and forms the oxide giving the blue color, which turns red on all those parts exposed to the air. To make this soap, proceed very much as for the white soap. To the melted grease pour on the 50 pounds of the weaker lye at 15°, gently raising the heat while they are mixing, which should be done by gently stirring, and keeping down the froth by beating, and regulating the heat to prevent too rapid boiling. After three or four hours, pour in the 50 pounds of lye at 21°, and continue the stirring, and as the froth subsides bring to a more rapid ebullition, and when it granulates shut off the heat and let it rest for four or five hours. Now draw off the sub-lye and proceed to the coction, by putting into the melted soap the third 50 pounds of lye at 27°, which is added while constantly beating and stirring. Stir in also 5 pounds of common salt, and continue the boiling for six or eight hours, as may be required, or until the grains separate, as can be seen by taking out a portion with a knife or pressing between the fingers, when a little experience will show a flakey scale free from the lye ; let the heat be stopped and the soap allowed to settle until next day, when after drawing off the salted lye it can be finished. The soap is finished with weak sal-soda lye, or, if the soap is neutral, with water having a little salt in solution, for if it needs water the grains will appear hard and dry, when the soap will have to be boiled until it forms a smooth mass. The soap is again allowed to rest, and the next day again thoroughly stirred and put in the frame, when it is ready for the mottling. This is done by putting into a small watering-pot with a rose-spout about 4 ounces of sulphate of iron, dissolved in a pint of warm water, and pouring it from the rose on to the top of the soap in the frame, while the crutch is plunged up and down to give the streaky 301 300 TECHNICAL TREATISE ON SOAP AND CANDLES. marbled appearance. Of course this requires some practice, as it should present a uniformity throughout the entire mass, but is not difficult to accomplish with a little experience. If this soap is carefully made, it will be as good as most of the mottled Castile soaps we import, and should be made so economically as to yield a good profit while being sold at a less price than the imported article. We have devoted some space to the description of the manufacture of these soaps from cotton-seed oil, believing that the cheapness and other advantages of the raw material will induce soap-makers to give it the consideration it seems to deserve for making a good and cheap soap, and that they may see a source of profit in its manufacture. THE FABRICATION OF SOAPS. SECTION XII. THE FABRICATION OP SOAPS (CONTINUED). EXTEMPORE AND OTHER SOAPS. EXTEMPORE soaps, as we term them, are called in France little pan-soaps, because they can be made in the smallest quantity. They differ from the boiled soaps in containing all the glycerine that may be in the neutral fat, which, as we have showrn, is precipitated with the sub-lye in the process of separation with culinary salt, or by other means. Thus, soaps are made in several ways, but, by whatever mode it is necessary clearly to calculate the requisite quantity of alkali, for the saponifi-cation of a given quantity of fats, or the equivalents. "When this is done, and the proper skill is used, the result is generally satisfactory, although such soaps are never so neutral as those made by boiling. On the score of economy there are divers opinions, while much time is saved, and the necessary plant is not near so costly, there is some additional expense in the preparation of the lye, yet on the whole, we would say that they cost less to make, than the soaps made by boiling, particularly at the present time, when the alkalies are obtained with so much facility. These soaps are now made largely in nearly all commercial countries. Under this head may be classed all these soaps called half-boiled soaps, which we consider better entitled to the name we propose, Extempore soaps, as they are made with rapidity and retain their glycerine. Thus, when cocoa-nut oil enters into their composition, it is customary to saponify it separately in strong lye, and add it to the previously boiled tallow, or tallow and palm oil, or rosin, which have been boiled in a lye of 15° to 21° B. They are also marbled in the frame 302 Previous Next
|
|
