Cooley's Cyclopaedia of Practical Receipts Volume Ii Part 216

=Soap, Naples.= From olive oil and potash.

=Soap, Orange-flower.= As SAVON a LA ROSE, with oil of neroli or essence de pet.i.t grain, supported with a little of the essence of ambergris and Portugal, for perfume.

=Soap, Palm-oil.= _Syn._ VIOLET SOAP. Made of palm oil and caustic soda lye. It has a pleasant odour of violets and a lively colour.

=Soap, Pearl.= _Syn._ ALMOND CREAM; CReME D'AMANDES, Fr. _Prep._ From a soap made of lard and caustic potash lye; when quite cold it is beaten in small portions at a time in a marble mortar, until it unites to form a h.o.m.ogeneous ma.s.s, or 'pearls,' as it is called; essence of bitter almonds, q. s., to perfume, being added during the pounding.

=Savon a la Rose.= [Fr.] _Prep._ From a mixture of olive-oil soap, 36 lbs.; best tallow soap, 24 lbs. (both new and in shavings); water, 1 quart; melted in a covered bright copper pan, by the heat of a water bath, then coloured with vermilion (finely levigated), 2-1/2 oz.; and, after the mixture has cooled a little, scented with otto of roses, 3 oz.; essence of bergamot, 2-1/2 oz.; oil of cloves and cinnamon, of each 1 oz.

=Soap, Rondeletia.= This is merely cinnamon soap scented with the essence made with mixed essential oils, &c., known as rondeletia. It is coloured with brown or yellow ochre.

=Soap, Sha"ving.= See PASTE (Shaving).

=Soap, Transpa"rent.= _Prep._ From perfectly dry almond, tallow, or soft soap, reduced to shavings, and dissolved, in a closed vessel or still, in an equal weight of rectified spirit, the clear portion, after a few hours'

repose, being poured into moulds or frames; after a few weeks' exposure to a dry atmosphere, the pieces are 'trimmed up' and stamped, as desired. It may be scented and coloured, at will, by adding the ingredients to it while in the soft state. A rose colour is given by tincture of archil; and yellow, by tincture of turmeric or annotta. It does not lather well.

=Soap, Windsor.= _Syn._ SAPO VINDESORae, S. VINDESORIENSIS, L. _Prep._ 1.

(WHITE; S. V. ALBUS.) The best 'English' is made of a mixture of olive oil, 1 part, and ox tallow or suet, 9 parts, saponified by caustic soda.

'French Windsor-soap' is made of hogs' lard, with the addition of a little palm oil. That of the shops is merely ordinary curd soap, scented with oil of caraway, supported with a little oil of bergamot, lavender, or origanum. To the finer qualities a little of the essences of musk and ambergris is occasionally added. 1-1/2 lb. of the mixed scents is the common proportion per cwt.

2. (BROWN; S. V. FUSCUS.) This merely differs from the last in being coloured with burnt sugar, or (less frequently) with umber. Originally it was the white variety, that had become mellow and brown with age.

=SO'DA.= See SODIUM.

=SO'DIUM.= Na. _Syn._ NATRIUM. The metallic base of soda. It was first obtained by Sir H. Davy, in 1807, by means of a powerful galvanic battery; but it may be more conveniently and cheaply procured, in quant.i.ty, by the method described under POTa.s.sIUM. The process, when well conducted, is, however, much easier and more certain than that for the last-named metal.

_Prep._ The anhydrous carbonate of sodium, 6 parts, is dissolved in a little water, and the solution mixed with charcoal in fine powder, 2 parts, and charcoal in small lumps, 1 part; the whole is then evaporated to dryness, transferred to an iron retort, and treated in the manner described at page 1353.

_Obs._ Very important improvements have been made in the manufacture of this metal by Deville, consisting partly in the simplification of the receiver, and partly in the addition of carbonate of calcium to the mixture, which addition appears to facilitate the reduction of the sodium in a most remarkable manner.

_Prop., &c._ Sodium is a soft silver-white metal, scarcely solid at common temperatures, fuses at 194 Fahr., and volatilises at a red heat; it oxidises very rapidly in the air; when placed on the surface of cold water, it decomposes that liquid with great violence, but generally without flame, in which it differs from pota.s.sium; on hot water it burns with a bright yellow flame--in both cases a solution of pure soda being formed. Sp. gr. 972; it is more malleable than any other metal, and may be easily reduced into very thin leaves (Ure); its other properties resemble those of pota.s.sium, but are of a feebler character. With oxygen it forms two oxides; with chlorine, a chloride (common salt); and--with bromine, iodine, fluorine, &c., bromide, iodide, fluoride, &c., all of which may be obtained by similar processes to the respective compounds of pota.s.sium, which, for the most part they resemble.

_Uses._ Until recently sodium has been regarded as a mere mechanical or philosophical curiosity; it has now, however, become of great practical importance, from being employed in the manufacture of the metals aluminium, magnesium, &c.

_Tests._ Sodium salts are recognised by their solubility in water, and by their giving a precipitate with none of the ordinary reagents. They give a rich yellow colour to the colourless Bunsen or the pale blue blowpipe flame. They can, to a certain extent, be also distinguished from pota.s.sium salts by the carbonate being an easily crystallisable salt, effervescing in dry air; the carbonate of pota.s.sium being crystallised with difficulty, and deliquescent. Platinum chloride does not give a precipitate with sodium chloride; neither does picric acid, perchlorate of ammonium, nor tartaric acid.

=Sodium, Acetate of.= NaC_{2}H_{3}O_{2}. _Syn._ ACETATE OF SODA; SODae ACETAS (B. P., Ph. D.), L. Prepared from carbonate of sodium as the corresponding pota.s.sium salt; but the resulting solution is evaporated to a pellicle, and set aside to crystallise. Its crystals are striated oblique rhombic prisms; it effloresces slightly in the air, and is soluble in 4 parts of water at 60 Fahr. Diuretic.--_Dose_, 20 to 40 gr.

=Sodium, Aluminate.= This salt has of late been in extensive demand by the calico printer and dyer. In France it is obtained from banxite, a native hydrate of aluminate, by treatment with caustic or carbonate of soda. If caustic soda be employed, the powdered banxite is boiled with a solution of the alkali, whereas if carbonate of soda be used, it is fused with the banxite in a reverbatory furnace. By the first process the resulting aluminate of soda is dissolved in water, and evaporated to dryness, forms the commercial article. If prepared by ignition, the semifused ma.s.s is lixiviated with water, and then evaporated to dryness. Aluminate of soda prepared as above occurs as a white powder, of a greenish-yellow hue, and dry to the touch.

It is equally soluble in both hot and cold water, and readily decomposed by carbonic and acetic acids, bicarbonate and acetate of soda, chloride of ammonia, &c. Dr Wagner states that it is used for the preparation of lake colours, the induration of stone, in the manufacture of artificial stone, and for the saponification of fats in the manufacture of stearin candle manufacture, also in the preparation of an opaque, milky-looking gla.s.s, or semi-porcelain.

Aluminate of soda may likewise be procured from cryolite, as described under ALUM.

=Sodium a.r.s.eniates.= _Syn._ SODae a.r.s.eNIAS (B. P.). a.r.s.enious acid, 10 oz.; nitrate of soda, 8-1/2 oz.; dried carbonate of soda, 5-1/2 oz.; boiling distilled water, 35 fl. oz. Reduce the dry ingredients separately to fine powder, and mix them thoroughly in a porcelain mortar. Put the mixture into a large clay crucible and cover it with the lid. Expose it to a full red heat till all effervescence has ceased, and complete fusion has taken place. Pour out the fused salt on a clean flagstone, and as soon as it has solidified and while it is still warm put it into the boiling distilled water, stirring diligently. When the salt has dissolved filter the solution through paper, and set it aside to crystallise. Drain the crystals, and having dried them rapidly on filtering paper, enclose them in a stoppered bottle.

=Sodium, Benzoate.= _Syn._ SODae BENZOAS. (B. Cod.) _Prep._ Heat gently benzoic acid and water, and add caustic soda, q. s. to neutralise the acid. Filter, evaporate, and crystallise over sulphuric acid under a bell-gla.s.s.

=Sodium, Bisulphate.= _Syn._ ACID SULPHATE, SODae BISULPHIS. _Prep._ Dissolve crystallised carbonate of soda in twice its weight of water, and pa.s.s sulphurous acid in excess through the solution. Set it aside to crystallise. Its solution is used to preserve subjects.

=Sodium, Bromide of.= _Syn._ SODII BROMIDUM. Prepared as bromide of pota.s.sium.

=Sodium, Carbonate of.= Na_{2}CO_{3}. 10Aq. _Syn._ CARBONATE OF SODA, MONO-CARBONATE OF SODA, SUBCARBONATE OF S., Salt of barilla; SODae CARBONAS (B. P., Ph. L., E., & D.), L. The carbonate of sodium of commerce (WAs.h.i.+NG SODA) was formerly prepared from the ashes of seaweed, and other marine vegetables, in a somewhat similar manner to that by which carbonate of pota.s.sium is obtained; but it is now usually obtained from chloride of sodium by the action of heat, sulphuric acid, and carbonaceous matter.

[Ill.u.s.tration: Scotch Soda Furnace.]

_Prep._ 1. (From common salt or sulphate of sodium.) The latter is generally obtained by decomposing the former with sulphuric acid, the evolved gas being pa.s.sed into water, or through flues filled with c.o.ke, over which a very small stream of cold water constantly flows, by which it is condensed, and forms 'LIQUID HYDROCHLORIC ACID,' a substance afterwards consumed, in large quant.i.ties, in the manufacture of chloride of lime, and for other purposes. The sulphate of sodium, obtained from this or any other source, is well mixed with an equal weight of chalk or limestone, and about half its weight of small coal, each being previously ground to powder, and the mixture is exposed to a strong heat in a 'reverbatory furnace' (see _engr._) until the decomposition of the sulphate is complete, the ma.s.s during the calcination being frequently stirred about with a long iron rod; the semi-liquid is now raked into an iron trough, where it is allowed to cool, whilst the furnace is recharged with fresh materials. The crude dark-grey product, thus obtained, is known as 'ball alkali,' or 'British barilla,' and usually contains about 22 or 23% of pure hydrate of sodium. This is now lixiviated with tepid water, and the solution, after defecation, evaporated to dryness; the residuum is mixed with a certain quant.i.ty of sawdust, coal-dust, or charcoal, and roasted in a reverberatory furnace, at a heat not exceeding 700 Fahr., until all the sulphur is expelled. The product is the 'soda-ash,' 'soda salt,' or 'British alkali,' of commerce, and contains about 50% of pure sodium, partly in the state of carbonate, and partly as hydrate, the remainder being chiefly sulphate of sodium and common salt. When this is purified by solution in water, defecation, evaporation, and crystallisation, it furnishes commercial crystallised carbonate of soda. When this last is redissolved, and the filtered solution is carefully crystallised, it const.i.tutes the ordinary carbonate of sodium used in pharmacy and medicine.

Another process for the preparation of commercial carbonate of sodium, known as the 'ammonia process,' has of late years met with considerable adoption. The history of this process, together with the process itself, are thus described by Dr R. Wagner:[175] "Six years ago (he was writing in 1873), when the international jury at the Paris Exhibition expressed their opinion upon the state of the soda industry at that time, all the judges, whether practical or theoretical men, believed that Leblanc's process (that previously described) would hold the field for a long time yet. This seemed still more probable, since a process had just been introduced for recovering the sulphur from the soda residues. At that time all the soda in use was prepared by this process, excepting a comparatively small amount obtained from Chili saltpetre and cryolite, although there were already tangible indications that soda could be made on a larger scale by another method, which would be cheaper than Leblanc's process.

[Footnote 175: 'Journal of Applied Chemistry.']

"The chemical section of the international jury at the Vienna Exposition, under the presidency of Professor A. W. Hofmann, const.i.tuted a congress of chemical technology. By its labours during the course of the summer this congress of scientific men was able to authenticate the very important fact that although Leblanc's process might in the future possess some importance for certain branches of the industry, yet in most places another soda process would be introduced in the immediate future, and entirely supersede that of Leblanc. Since the time of the Paris Exhibition this new process has grown from a small germ to a strong tree.

"The process in question, and which is called by Professor Hofmann 'the ammonia process,' is not new, from either a chemical or scientific point of view. It belongs to the same methods as those in which oxide of lead, bicarbonate of magnesia, quicklime, alumina, silicate of alumina, oxide of chromium, or fluosilicic acid are employed to decompose chloride of sodium, and convert it directly into soda or its carbonate. None of these attempts met with a success deserving of notice; although for a century past efforts have been made to render them practically operative. The new process is founded upon a reaction noticed over thirty years ago--that of bicarbonate of ammonia upon a strong solution of common salt. The greater part of the sodium is precipitated as bicarbonate, while chloride of ammonium remains in solution, from which the ammonia for a second operation is expelled by quicklime. The carbonic acid necessary to convert the ammonia into bicarbonate of ammonia, and thus make the process a continuous one, is obtained by heating the bicarbonate of soda to convert it into the simple carbonate.

"The sensation which the ammonia process has created in industrial circles will render a brief history of its development not uninteresting.

"So far as I know, Harrison, Dyer, Grey, and Hemming were the first to patent the ammonia process in Great Britain in 1838. Great expectations were excited by it, but it soon sank into oblivion.

"Thirty or forty years ago the manufacture of soda was by no means at the head of the great branches of industry; at that time, too, ammonia was not to be had cheaply and in immense quant.i.ties, and that branch of machine building which has furnished the necessary apparatus for chemical industries did not exist. Besides this, Anton, of Prague, in 1840, claimed to have proved that in the ammonia process a very considerable portion of the common salt still remained undecomposed.

"After a sleep of sixteen years the ammonia process again entered the field. On the 26th of May, 1854, Turck took out a patent in France, and on the 21st June, the same year, Schlsing, chemist of the Imperial Tobacco Factory at Paris, took out a patent for France and Great Britain. The mechanical portion and machinery for Schlsing's process were designed by Engineer E. Rolland, director of the tobacco factory. In 1855 a company was organised to work this process. An experimental manufactory was started at Puteaux, near Paris, but, owing to its situation and arrangements, as well as the salt monopoly, it could not produce soda cheap enough to compete with the other process, and hence, in 1858, the experiment was abandoned. Schlsing and Rolland were of the opinion that sooner or later the new process must come into use in making soda.

"It must here be noticed that in 1858 Professor Heeren, of Hanover, subjected the ammonia process to a very careful test in his laboratory.

"From his experiments and calculations it was ascertained that this process was better adapted to the manufacture of the bicarbonate than of the simple protocarbonate of soda.

"To render this sketch more complete and historically true, it must be mentioned that T. Bell, of England, took out a patent, Oct. 13th, 1857, for a new soda process, which in principle and practice was almost literally the same as that of Dyer.

"It was known when the jury was working at Paris in 1867 that essential improvements had been introduced into the ammonia process by the efforts of Marguerite and De Sourdeval, of Paris, and James Young, of Glasgow. A more important fact, however, is that Solvay and Co., of Conillet, in Belgium, actually exhibited at the Paris Exhibition carbonate of soda prepared by this new process.

"Since that time the ammonia process has been developed and perfected to such an extent, especially by Solvay, Honigmann, and Prof. Gerstenhfer, that as early as February, 1873, A. W. Hofmann, in his introduction to the third group of the catalogue of the Exhibition of the German Empire, was able to make this remark:--'At all events the ammonia process is the only one which threatens to become an important compet.i.tor of the now also most exclusively employed process of Leblanc.' The Vienna Exposition has since proved the truth of this a.s.sertion.

"There are now large works in England, Hungary, Switzerland, Westphalia, Thueringia, and Baden, which employ the improved ammonia process, and some of them make fifteen tons of soda per day.

"The advantages of the new process over that of Leblanc are very evident, although the details of the process have not yet been made public.

"The chief advantage consists in the direct conversion of salt into carbonate of soda, and next from the fact, that from a saturated brine only the sodium is precipitated, with none of the other metals of the mother liquor. Besides this, the product is absolutely free from all sulphur compounds, the soda is of a high grade, the apparatus and utensils are very simple, there is a great saving of labour and fuel, and no noxious gases and waste products are produced, which is of importance from a sanitary point of view. The only weak point of the ammonia process is the loss of chlorine, which is converted into worthless chloride of calcium.

"The effect which the general introduction of the new soda process will exert upon large chemical industries in general, and especially upon the consumption of sulphur, the manufacture of sulphuric acid, and chloride of lime, cannot be overlooked."

3. Another method for the direct preparation of soda and potash from their chlorides is described in the 'Bayerisches Industrie und Gewerbe Blatt.'[176] The process is thus described by its author, Herr E. Bohlig:

[Footnote 176: 'New Remedies,' 1878, 4.]

1. Magnesium oxalate (freshly prepared when newly starting, but, after the first operation, obtained as a dry product in the next step) is allowed to drain, and then mixed in a large vat with the proper quant.i.ties of sodium chloride, or concentrated brine and hydrochloric acid, after which it is allowed to stand a few hours. Decomposition takes place almost instantaneously; all the magnesium goes into solution in form of syrupy magnesium chloride, while all the sodium and oxalic acid are deposited as a crystalline acid salt (acid sodium oxalate, or binoxalate of sodium).