Antimony trisulphide

It is recommended that the eompound be fused with a mixture of sodium carbonate (2 parts) and sodium peroxide (1 part) as in the test for Plvoaphoms. Extract the fused mass with water, filter, and acidify with dilute hydrochloric acid. Pass hydrogen sulphide through the hot solution arsenic is precipitated as yellow arsenic sulphide. If antimony is present, it will be precipitated as orange antimony trisulphide. 

There are the same typically dangerous reactions as with sulphides. Antimony pentasuiphide is not mentioned in the specialised literature, but it is unlikely that it behaves in a different way from the trisulphide. Antimony trisulphide can produce dazzling white flames. This is the reason it is used in pyrotechnics. 

Antimony trisulphide combusts spontaneously when it is ground up with silver(l) oxide. 

Vanadium pentoxide sols can be employed to bring about coagulation of positively charged colloids for example, ferric hydroxide and aluminium hydroxide. The amount necessary for the coagulation of a given quantity of the positive colloid is very small in comparison with the required quantities of arsenic trisulphide, antimony trisulphide, and other negative colloids. It appears, therefore, that the colloidal... 

Hydrogen sulphide orange-red precipitate of antimony trisulphide, Sb2S3, from solutions which are not too acid. The precipitate is soluble in warm concentrated hydrochloric acid (distinction and method of separation from arsenic(III) sulphide and mercury(II) sulphide), in ammonium polysulphide (forming a thioantimonate), and in alkali hydroxide solutions (forming antimonite and thioantimonite). 

Zinc a black precipitate of antimony is produced. If a little of the antimony trichloride solution is poured upon platinum foil and a fragment of metallic zinc is placed on the foil, a black stain of antimony is formed upon the platinum the stain (or deposit) should be dissolved in a little warm dilute nitric acid and hydrogen sulphide passed into the solution after dilution an orange precipitate of antimony trisulphide will be obtained. 

Lavik et al ° reported up to 400% improvement in wear life, and lower friction at high or low temperature, when antimony trioxide was used in polyimide or polybenzothiazole-bonded films. Lower improvements, up to 270%, were obtained with antimony trisulphide, while Bartz reported that the addition of both graphite and antimony tetrasulphide (or antimony thio-antimonate Sb(SbS4)) gave a much greater improvement in the life of a polybutyltitanate-bonded molybdenum disulphide film than either of the additives separately. 

Potassium chlorate becomes quite sensitive in contact with red phosphorus and ignites very easily by friction. These properties are used in match. When it is mixed with sulphur or compounds of sulphur like realgar, antimony trisulphide etc., the sensitivity to shock or friction is highly increased. According to the late professor S.Yamamoto of Tokyo University, when a mixture of potassium chlorate and realgar was shaped into a small tablet in a hand press and left on a table, a little while later the tablet caused spontaneous ignition and burnt out. He tried the same tests sevejjral times and the results were the same. He concluded that it was caused by inner friction which occurs with the recovery of the stress produced by the press(s. Yamamoto Studies in safety in firework manufacture 1(1959)3 ... 

Potassium perchlorate becomes sensitive in contact with red phosphorus the mixture detonates with a loud noise by an impact between metal pieces of aluminium or bronze. When the mixture is ignited, it detonates instantaneously. However match or toy pistol caps cannot be made from compositions which contain potassium perchlorate in place of chlorate, because the ignition is uncertain. When potassium perchlorate is mixed with realgar, antimony trisulphide, sulphur etc. it also becomes sensitive realgar particularly increases the sensitivity to friction. But the degree of sensitivity is not as large as it is with potassium chlorate. 

When ammonium perchlorate is mixed with red phosphorus it becomes very sensitive to shock, but not so much to friction. With realgar, sulphur, antimony trisulphide etc. it also becomes sensitive almost like the above. The degree of shock sensitivity of ammonium perchlorate due to such substances is almost the same as that of potassium chlorate, but higher than that of potassium perchlorate. The low friction sensitivity of ammonium perchlorate due to these substances is one of its attractive features in comparison with potassium chlorate and perchlorate(T.Shimizu Sensitivity tests on firework compositions, J. Exp.Soc. Japan, 2, No.6, p. 3 3... 

The combustion heat is about 1000 kcal per 1 kg of antimony trisulphide, when SbiSi is oxidized to SO2, and Sb2,0j this is equal to about a half of the heat of sulphur. The maximum purity of natural antimony trisulphide is about 88%, and the practical heat of combustion may be lov/er than that. 

Antimony trisulphide burns in combination with ammonium perchlorate producing a slightly green flame(in the case of sulphur a slightly red flame) and can generate red brown smoke in combination with potassium nitrate and charcoal. 

Manufacture. Antimony trisulphide is obtained from stibnite which occurs naturally in Bolivia, China, Hungary, Southern Africa. 

The wet process is used for manufacturing cracker balls(the composition consists of realgar and potassium chlorate), paper caps (red phosphorus, sulphur and potassium chlorate) and pull-igniters (red phosphorus, antimony trisulphide and potassium chlorate). 

The boric acid prevents the potassium nitrate and aluminium from reacting v ith each other(R.Lancaster Fireworks, p.31(1972)). No.l and No.2 produce a pretty golden fire dust. No.3 produces a somewhat reddish gold effect, and looks more elegant than Nol and No.2. When we use antimony trisulphide, sulphur and realgar, as components in one composition with various ratios between them, various colour tones of gold can be obtained. 

Compositions. Red phosphorus, sulphur, realgar, antimony trisulphide or other sulphides should possibly be rejected from the compositions. It is the same to chlorates also. These materials increase the sensitivity of almost all compositions. However in practice, the requirement is not always satisfied sufficiently, and each one must be considered individually. The sensitivities in Table 28, 29 and 30(Chapter 27) may be used for planning compositions correctly. On the other hand, select each of the components so that no chemical reaction can occur among the materials. Generally a mixture of metal powder and oxidizer or chloride will cause a chemical reaction to evolve heat in presence of water. Metal powder is sometimes damaged by corrosion, and generally the grains must be coated by some... 

The ratio of the oxidizer to the fuel(by weight) also has an influence upon the sensitivity. Note however that in the case of red phosphorus, realgar, antimony trisulphide or sulphur the influence is quite small, and- ... 

The readers perhaps notice in Table 28 the fact that, if materials which give a high sensitivity like red phosphorus, realgar, sulphur, antimony trisulphide etc. are rejected from firework compositions, firework manufacture is made much safer. In these circumstances devices are always necessary, the problem being that without these materials ignition can be difficult in fireworks. This is one of the most important themes in fireworks. 

Antimony trisulphide is often used in place of sulphur, because the former causes little degeneration in contact with metal powder or containers(Fig.15 ) ... 

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