Sodium sulphide, anhydrous

Sodium plumbite solution, 1041 Sodium press, 164 Sodium sulphide, anhydrous, 197 use of, 574, 587... 

Anhydrous sodium sulphide. The hydrated salt, NajS.QH O, is heated in a Pyrex distilling flask or retort in a stream of hydrogen or of nitrogen until water ceases to be evolved. The solid cake of anhydrous sodium sulphide is removed from the vessel with the aid of a copper wire hook or by other suitable means. No attempt should be made to fuse the sodium sulphide since at high temperatiues sodium sulphide is readily oxidised to sodium sulphate. 

The alkyl sulphides or thioethers, the sulphur analogues of the ethers, are conveniently obtained by boiling alkyl halides with anhydrous sodium sulphide in alcoholic solution, for example ... 

Place 56 g. of finely-powdered, anhydrous sodium sulphide ( fused sodium sulphide) and 100 ml. of rectified spirit in a 500 ml. round-bottomed flask equipped with a reflux condenser. To the boiling mixture... 

Di-n-hexyl sulphide. Use 83 g. (71 ml.) of n-hexyl bromide (Section III.37), 56 g. of finely-powdered, anhydrous sodium sulphide and 100 ml. of rectified spirit. Reflux on a water bath for 20 hours. Distil ofiF the alcohol from a water bath very Uttle sulphide is obtained upon adding excess of water to the distiUate. Add excess of water to the residue in the flask and separate the upper layer of crude n-hexyl sulphide. Purify as for n-propyl sulphide, but distil under reduced pressure. CoUectthe n-hexyl sulphide at 113-114°/4 mm. The yield is 45 g. 

Place 84 g. of iron filings and 340 ml. of water in a 1 - 5 or 2-litre bolt-head flask equipped with a mechanical stirrer. Heat the mixture to boiling, stir mechanically, and add the sodium m-nitrobenzenesulphonate in small portions during 1 hour. After each addition the mixture foams extensively a wet cloth should be applied to the neck of the flask if the mixture tends to froth over the sides. Replace from time to time the water which has evaporated so that the volume is approximately constant. When all the sodium salt has been introduced, boU the mixture for 20 minutes. Place a small drop of the suspension upon filter paper and observe the colour of the spot it should be a pale brown but not deep brown or deep yellow. If it is not appreciably coloured, add anhydrous sodium carbonate cautiously, stirring the mixture, until red litmus paper is turned blue and a test drop upon filter paper is not blackened by sodium sulphide solution. Filter at the pump and wash well with hot water. Concentrate the filtrate to about 200 ml., acidify with concentrated hydrochloric acid to Congo red, and allow to cool. Filter off the metanilic acid and dry upon filter paper. A further small quantity may be obtained by concentrating the mother liquid. The yield is 55 g. 

Tetrabromoperfluorotelluranthrene (0.5 g, 0.57 mmol) and excess sodium sulphide non-ahydrate are placed in a flask and the flask is heated in a water bath at 90°C for 20 min. The resultant reaction mixture is cooled to 20°C and extracted with portions of diethyl ether (2X25 mL). The combined ether extracts are dried with anhydrous sodium sulphate, filtered, the filtrate is evaporated under vacuum, the residue is sublimed, and the sublimate is recrystaUized from absolute methanol. Yield 0.065 g (20%) m.p. 119°C. 

The solubility of sodium sulphide in water, studied by N. Parravano and M. Fornaini, shows a cryohydrate temp.—10° when 9 34 per cent, of anhydrous sulphide is present in soln. The enneahydrate exists in aq. soln. up to 48 9°, where it is transformed into the hemihenahydrated sodium sulphide, Na2S.5 H20, which exists in a labile condition between 48 9° and 91 5°, and is stable between 91 5° and 94°. The hexahydrated sodium Sulphide, Na S.eH O, is stable between 48° and 91 5° but the enneahydrate does not change into the hexahydrate at 48°, rather... 

Place 56 g (0.5 mol) of finely powdered, fused sodium sulphide and 100 ml of rectified spirit in a 500-ml round-bottomed flask equipped with a reflux condenser. To the boiling mixture add 46 g (34 ml, 0.374 mol) of propyl bromide slowly and reflux for 6 hours. Distil off the ethanol on a water bath, and add a large excess of water to the distillate. Separate the upper layer of crude sulphide, wash it with three 40-ml portions of 5 per cent sodium hydroxide solution, then with water until the washings are neutral, and dry over anhydrous calcium chloride or anhydrous calcium sulphate. Distil, and collect the dipropyl sulphide at 141-143 °C. The yield is 20g (91%). If the sulphide is required perfectly pure, it should be redistilled from a little sodium. 

It is a white, crystalline solid, very deliquescent, freely soluble in water, and moderately soluble in alcohol. When exposed to air it evolves hydrogen sulphide,1 and is completely decomposed by heat into this gas and sodium monosulphide.2 The anhydrous salt is also obtained by the interaction at 300° C. of sodium monosulphide and hydrogen sulphide free from carbon dioxide and oxygen.3 Sabatier s4 method is to saturate a solution of sodium sulphide with hydrogen sulphide, and concentrate in an atmosphere of the same gas. A solution can be obtained by saturating sodium-hydroxide solution with hydrogen sulphide. A dihydrate and a trihydrate have been described.5... 

SYNS SODIUM MONOSULFIDE SODIUM SULFIDE, anhydrous (DOT) SODIUM SULFIDE with <30% water of crystallization pOT) SODIUM SULPHIDE... 

What became known as the Leblanc process was actually several interrelated processes. Salt was first reacted with sulphuric acid in a cast-iron pan, then in a reverberator furnace (in which heat was apphed from a flame blown from a separate chamber, not in direct contact with the salt), to produce saltcake (sodium sulphate), with hydrochloric acid released as a waste gas. Saltcake was used to make sodium carbonate, or roasted with limestone (calcium carbonate) and coal or coke to produce black ash. This mixture of sodium carbonate, calcium sulphide, sodium sulphide, hme, salt, carbon, and ash could be treated further with hot water to produce impure sodium carbonate in solution, evaporated into soda crystals (washing soda), or heated to yield anhydrous sodium carbonate. The latter, in turn, could be reacted with lime to made caustic soda (sodium hydroxide), the strongest commercial alkali then available. 

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