Cooley's Cyclopaedia of Practical Receipts Volume I Part 50

[Footnote 70: The like precipitate from a solution of antimonic acid in hydrochloric acid, dissolves readily in ammonia, particularly when heated.]

[Footnote 71: See a.r.s.eNIOUS ACID.]

[Ill.u.s.tration:

_a_, Flask containing the suspected fluid, dilute sulphuric acid, and zinc.

_b_, Small tube, at the one end having an almost capillary orifice, where the gas is inflamed.

_c_, Spirit-lamp.

_d_, Support.]

_Estim._ Antimony is generally WEIGHED under the form of tersulphide; but sometimes as antimonious anhydride, and--though more seldom--as pure metal:--

1. A solution being obtained as above, if necessary, it is strongly acidulated with tartaric acid, and the antimony thrown down as a sulphide by a stream of sulphuretted hydrogen. After warming the solution and allowing it to cool, the precipitate (TERSULPHIDE) is collected on a filter, dried, and weighed. A small portion digested in strong hydrochloric acid will completely dissolve if it be the pure sulphide; in which case the quant.i.ty of ANTIMONY sought will be equal to 71-1/2% (715%) of the weight of the sulphide found (very nearly).[72] Should only part of the precipitate be soluble, a known weight of it may be introduced into a flask, and a considerable quant.i.ty of fuming nitric acid added, drop by drop, and afterwards, a little hydrochloric acid, the mixture being digested, at a gentle heat, until the reaction is complete, and the whole of the sulphur is dissolved. The resulting solution diluted with water, strongly acidulated with tartaric acid, and solution of chloride of barium added as long as it disturbs the liquid, yields a precipitate, of which the weight, after it has been thoroughly washed, dried, and gently ignited, multiplied by 136, gives the quant.i.ty of SULPHUR in the sample; and which, deducted from the weight of the sulphide first found, gives the quant.i.ty of pure ANTIMONY, as before.

[Footnote 72: Tersulphide of antimony dried at 212 Fahr. still retains traces of water, which is not wholly expelled until the heat reaches 390-392, when it acquires a black colour and a crystalline appearance.]

2. The quant.i.ty of PURE ANTIMONY in commercial samples may be determined by treating them (in powder) with nitric acid, which oxidises the antimony and leaves it in an insoluble state, whilst it dissolves the other metals.

The resulting oxide is collected on a filter, washed, dried, ignited in an open porcelain crucible, and weighed--its weight multiplied by 7898 gives the quant.i.ty of pure metal sought.

3. Dissolve a known weight of the sample in hydrochloric acid, immerse a blade of pure metallic tin in the solution, and keep the liquor acidulous, and in a state of gentle ebullition by the heat of a sand bath, when the whole of the ANTIMONY will be precipitated under the form of a black powder, and may be collected, washed, dried, and weighed. This is particularly adapted to alloys of antimony and tin. See _Tests_ (above) and _Pur._ (below).

_Pur._ The antimony of commerce generally contains a little a.r.s.enic, with variable quant.i.ties of iron, lead, sulphur, and tin. These impurities may be thus detected:--

1. (a.r.s.enic.) By fusing the sample, in powder, mixed with about an equal weight of tartrate or bitartrate of pota.s.sium, in a covered crucible, for 2 or 3 hours, and placing the resulting b.u.t.ton, which is an alloy of antimony and pota.s.sium, in a 'Marsh's apparatus' along with a little water, when the disengagement of hydrogen gas will commence, and may be tested in the usual manner. See a.r.s.eNIC.

2. (Iron.) Dissolve the powdered sample in nitrohydrochloric acid, dilute the solution with a large quant.i.ty of cold water, filter, and pa.s.s a current of sulphuretted hydrogen through the filtrate as long as it produces a precipitate; again filter, boil the filtered liquor for a few minutes to drive off the sulphuretted hydrogen, and then test it with ferrocyanide of pota.s.sium, which will give a blue precipitate if iron be present; or supersaturate the last filtrate with ammonia, and then add hydrosulphydrate of ammonium, when, under like conditions, a black precipitate will be formed.

3. (Lead.) Digest the powdered sample in hot nitric acid, which will dissolve out the LEAD but leave the antimony behind. The whitish powdery residuum may be washed, dried, ignited, and weighed, as above; the clear decanted liquor may now be mixed with the first washings, evaporated to dryness, the residuum re-dissolved in water, and the solution submitted to reagents (see LEAD). If lead is found to be present, a solution of sulphate of sodium may be added until it ceases to disturb the liquid, and the resulting precipitate (sulphate of lead) washed, dried, and gently ignited (alone) in a porcelain crucible; the weight of the ignited residuum furnishes a number which, multiplied by 683, gives the weight of the LEAD sought.

4. (Sulphur.) The solution in nitrohydrochloric acid, when tested with either nitrate or chloride of barium, gives a white precipitate of sulphate of barium, insoluble in both water and acids, which when dried, ignited, and weighed, and the weight multiplied by 136, gives the quant.i.ty of SULPHUR as before. In this case, as with the sulphides (see _above_), free sulphur maybe removed by digesting and washing the powdered sample in bisulphide of carbon, previous to its solution in the acid, by which the violence of the subsequent reaction will be lessened.

5. (Tin.) Two samples of equal weight are taken; the one is tested for ANTIMONY, as described above; the other is dissolved in a mixture of equal parts of hydrochloric and nitrohydrochloric acid, and a blade of zinc immersed in the solution (see _above_); the mixed precipitate of tin and antimony which forms is collected on a weighed filter, washed, dried, and weighed. The weight of antimony in the first sample subtracted from that now obtained, leaves a remainder which indicates the quant.i.ty of TIN in the original sample.

_Phys. eff., &c._ Nearly all the salts and preparations of antimony are emetic and cathartic, and in large doses poisonous--occasioning vomiting, profuse alvine dejections, acute colic, and inflammation of the stomach and bowels, often serious, though rarely resulting in death. TARTAR EMETIC and b.u.t.tER OF ANTIMONY are those from which accidents have princ.i.p.ally occurred.--_Ant., &c._ Copious vomiting, if it has not already occurred, should be promoted, and the recently prepared hydrated sulphide of iron administered in considerable doses, followed or accompanied by mucilaginous drinks and diuretics. If much prostration follows, wine and stimulants may be had recourse to. In the absence of hydrated sulphide of iron, a solution of tannin, or decoction of galls; cinchona, or oak bark, or even powdered cinchona, mixed with tepid water, may be administered.

_Uses._ In the _arts_, antimony enters into the composition of several useful alloys, as TYPE-METAL, PEWTER, BRITANNIA-METAL, MUSIC-PLATE METAL, &c. It is added to the alloy for concave mirrors, to give them a finer texture; to bell metal, to render it more sonorous; and to various other metals to increase their hardness and fusibility; for the latter purpose it is employed in the casting of cannon b.a.l.l.s.

_Concluding Remarks._ In 'roasting' or oxidising the native sulphide of antimony on the bed of the reverberatory furnace, as in the common method before referred to, care must be taken to regulate and gradually raise the heat, which, until towards the end of the process, need not be extreme, and then only should it approach dull redness. Without this precaution much of the undecomposed sulphide will be lost by volatilisation. During the whole time the 'charge' should also be well stirred with an iron spatula, to ensure the constant exposure of every part of it to the atmosphere. The process is complete when the whole ma.s.s a.s.sumes a greyish-white appearance. Earthen crucibles are commonly employed for the subsequent reduction, and after being charged and covered over with ground charcoal, are heated in a reverberatory furnace. The product is the crude metallic antimony of commerce. It is generally REFINED by smelting it with about 1-8th of its weight of the refined sulphide, and about 1-4th of its weight of carbonate or sulphate of soda; but if there be much iron present, more of the sulphide--even 1-4th--may be required; for unless there be sufficient sulphur to combine with the whole of the iron, the a.r.s.enic will not be oxidised, but remain as a contamination. When cold, the metal is carefully separated from the slag, and is frequently re-fused with a little fresh carbonate of soda (1 to 1-1/2 part); after which it is cast into pigs, lumps, or ingots. The crude metal, thus treated, commonly yields 94% of REFINED METAL of tolerable purity.

Should lead have been present in the sulphide or ore, it remains after a second, or even a third fusion, although proportionately reduced in quant.i.ty; and it can only be completely separated in the humid way. It is, therefore, always desirable to select an ore free from lead.

=Antimony, Ash of.= _Syn._ ANTIMONY-ASH, CALCINED' ANTIMONY*; CI'NIS ANTIMO"NII, ANTIMO"NIUM CALCINA'TUM*, L. Prepared by roasting the common grey sulphide of antimony on an iron plate set under a chimney, to carry off the fumes. The product is a mixture of teroxide of antimony, with some unburnt sulphide, and a little antimonious acid.

_Prop., &c._ Ash-grey; emetic in small doses. Used chiefly as a cheap subst.i.tute for teroxide of antimony by the manufacturers of tartar emetic; also to make metallic antimony.

=Antimony, b.u.t.t'er of.= See ANTIMONY, TRICHLORIDE OF.

=Antimony, Calx of.= _Syn._ CALX ANTIMO"NII, L. Sometimes applied to antimony-ash, but more commonly to crude, unwashed diaph.o.r.etic antimony.

=Antimony, Calx of= (Sul'phurated). _Syn._ ANTIMO"NII CALX SULPHURA'TA, L. _Prep._ (Hufeland.) Calcined oyster-sh.e.l.ls, 10 parts; sulphur, 4 parts; crude antimony, 3 parts; powder, mix, and calcine in a luted crucible for an hour. Emetic, resolvent, and alterative.--_Dose_, 1 to 6 gr.; in gout, rheumatism, scrofula, &c.

=Antimony, Ce'ruse of.= _Syn._ ANTIMO"NII CERUS'SA, L. _Prep._ (Bate.) As diaph.o.r.etic antimony (over which it possesses no advantage), merely using the metal instead of the sulphide.

An old preparation made by igniting antimony in the sun's rays, by means of a lens, was called ANTIMONII CERUSSA SOLA"RIS.

=Antimony, Chlo"rides of= (klore'-idz):--

=1. Antimony, Trichloride of.= SbCl_{2}. _Syn._ TERCHLORIDE OF ANTIMONY, ANTIMONIOUS CHLORIDE, CHLO"RIDE OF ANTIMONY, SESQUICHLORIDE OF A., b.u.t.tER OF A., CAU'STIC ANTIMONY, &c.; ANTIMO"NII CHLORI'DUM, A. TERCHLORI'DUM, A. BU'TYRUM*, &c., L.; CHLORURE D'ANTIMOINE, BEURRE D'ANTIMOINE, &c., Fr.; ANTIMON-CHLORID, SPIESSGLANZ-b.u.t.tER, Ger. This is the substance of which common chloride, or b.u.t.ter of antimony, of the shops, is an impure concentrated solution containing free acid.

_Prep._ 1. SOLID, ANHYDROUS:--

_a._ Pure commercial tersulphide of antimony, in coa.r.s.e powder, 1 part; concentrated hydrochloric acid, 5 parts; are mixed in a capacious stoneware or gla.s.s vessel set under a chimney with a quick draught, to convey away the fumes, the whole being constantly stirred, and, as the effervescence slackens, a gradually increasing gentle heat applied until solution is complete; the resulting liquid is put into a retort, and distilled, until each drop of the distillate, as it falls into the aqueous liquid which has previously pa.s.sed over into the receiver, produces a copious white precipitate; the receiver is then changed, and the distillation continued, when pure TRICHLORIDE OF ANTIMONY pa.s.ses over, and solidifies on cooling to a white and highly crystalline ma.s.s, which must be carefully excluded from the air.

_b._ From pure metallic antimony, 2 parts; bichloride of mercury, 5 parts; both in fine powder; mixed and distilled in a retort with a large neck, by a gentle sand-heat, into a suitable receiver. Chemically pure.

2. LIQUID:--

_a._ (LIQUOR ANTIMONII CHLORIDI, B. P.) _Syn._ SOLUTION OF CHLORIDE OF ANTIMONY.

_Prep._ Take of black antimony, 1 _lb._; hydrochloric acid, 4 pints; place the black antimony in a porcelain vessel; pour upon it the hydrochloric acid, and, constantly stirring, apply to the mixture, beneath a flue with a good draught, a gentle heat, which must be gradually augmented as the evolution of gas begins to slacken, until the liquid boils. Maintain it at this temperature for fifteen minutes; then remove the vessel from the fire, and filter the liquid through calico into another vessel, returning what pa.s.ses through first, that a perfectly clear solution may be obtained. Boil this down to the bulk of two pints, and preserve it in a stoppered bottle.

_Characters and Tests._ A heavy liquid, usually of a yellowish-red colour.

A little of it dropped into water gives a white precipitate, and the filtered solution lets fall a copious deposit on the addition of nitrate of silver. If the white precipitate formed by water be treated with sulphuretted hydrogen it becomes orange-coloured. The specific gravity of the solution is 147. One fluid drachm of it mixed with a solution of a quarter of an ounce of tartaric acid in four fluid ounces of water, forms a clear solution, which, if treated with sulphuretted hydrogen, gives an orange precipitate, weighing, when washed and dried at 212, at least 22 grains.

_b._ (Commercial.)--_a._ Take of ash or calx of antimony, 3-1/4 _lbs._; common salt, 2 _lbs._; oil of vitriol, 1-1/2 _lb._; water, 1 _lb._; proceed as before. Prod., 2-1/2 _lbs._

_c._ From roasted sulphide or gla.s.s of antimony, 7 _lbs._; salt, 28 _lbs._; oil of vitriol, 21 _lbs._; water, 14 _lbs._; as before.

_d._ From crude sulphide of antimony (powdered), 25 _lbs._; strongest commercial hydrochloric acid, 1 _cwt._; nitric acid, 3-1/2 _lbs._; as before; the product being coloured with a little pernitrate of iron, and made up to the sp. gr. 14. The quality is improved, and the process more easily conducted, if the crude antimony is roasted before dissolving it in the acid. The same applies to the other formulae.

_Prop., &c._--_a._ SOLID. When pure, and nearly free from water, it somewhat resembles b.u.t.ter, melts with a gentle heat, and partially crystallises on cooling; is very deliquescent, and quickly pa.s.ses into an oily liquid when exposed to damp air; very soluble in strong hydrochloric acid; water, according to its quant.i.ty, more or less decomposes it. When perfectly pure and anhydrous, it forms a white and highly crystalline ma.s.s, rapidly decomposed by air and moisture.--_b._ SOLUTION. The sp. gr.

of the solution of the shops varies from 125 to 14, in which state it is a transparent fuming yellow liquid (unless when artificially coloured), and extremely acid and caustic. Submitted to distillation, it at first parts with its water and excess of acid, after which the salt itself is volatilised. By changing the receiver as soon as the distillate concretes on cooling, or produces a copious white precipitate on falling into the liquid already pa.s.sed over, the pure ANHYDROUS TRICHLORIDE may be readily obtained.

_Phys. eff., Ant., Lesions, &c._ See ANTIMONY.

_Uses._ In _medicine_, only externally, and chiefly as a caustic or escharotic to the wounds caused by rabid and venomous animals, and to repress excessive granulations in ulcers. In _pharmacy_, as a source of both oxychloride and oxide of antimony. The residuum in the retort when corrosive sublimate is used, is sulphide of mercury, and was formerly called CINNABAR OF ANTIMONY.

=2. Antimony, Pentachlo"ride of.= Sb_{2}Cl_{5}. _Syn._ PERCHLO"RIDE OF ANTIMONY; ANTIMO"NII PENTACHLORI'DUM, L. Prepared by pa.s.sing a stream of chlorine gas over metallic antimony in fine powder, and gently heated. A mixture of TRICHLORIDE and PENTACHLORIDE OF ANTIMONY is found in the receiver, from which the latter may be separated by careful distillation.

It is a colourless volatile liquid, forming a crystalline compound with a small quant.i.ty of water, but decomposed by a larger quant.i.ty.

=Antimony, Cro'cus of.= _Syn._ SAFF'RON OF ANTIMONY, LIV'ER OF A.; CRO'CUS ANTIMO"NII C. METALLO"RUM, HE'PAR ANTIMONII, L.; CROCUS D'ANTIMOINE, SAFFRAN D'A., Fr. _Prep._ 1. From black sulphide of antimony, and saltpetre, equal parts, deflagrated together by small portions at a time, and the fused ma.s.s (separated from the scoriae) reduced to fine powder.

2. (ANT. CROCUS, Ph. L. 1788,) Sulphide of antimony, 1 lb.; nitre, 1 lb.; common salt, 1 oz.; as before.

_Prop., &c._ Its medicinal properties closely resemble those of diaph.o.r.etic antimony. It is a mixture of sulphate of pota.s.sium, antimoniate of pota.s.sium, teroxide of antimony, oxysulphide of antimony, sulphide of pota.s.sium, and undecomposed trisulphide of antimony, in variable and undetermined proportions. When repeatedly washed or boiled in water, and dried, it forms the WASHED SAFFRON OF ANTIMONY (C. A. LO'TUS, L.) of old pharmacy, and has then lost its sulphate of pota.s.sium, caustic potash, and sulphide of pota.s.sium. Formerly used to make tartar emetic.

See ANTIMONY, LIVER OF.

=Antimony, Crude.= Native sulphide of antimony melted from the gangue.