Barium sulphide

The palladium may be recovered by heating the spent catalyst to redness in order to remove organic impurities this treatment may reduce some of the barium sulphate to barium sulphide, which acts as a catalytic poison. The palladium is then dissolved out with aqua regia and the solution evaporated the residue is dissolved in hot water and hydrochloric acid to form palladium chloride. 

Alkyl lithiums Dodecacarbonyltetracobalt Barium sulphide Triisopropylphosphine... 

Ammonium sulphide) Barium sulphide Calcium sulphide Chromium (II) sulphide Copper (II) sulphide Diantimony trisulphide Dibismuth trisulphide Dicaesium selenide Dicerium trisulphide Digold trisulphide Europium (II) sulphide Germanium (II) sulphide Iron disulphide Iron (II) sulphide Manganese (II) sulphide Mercury (II) sulphide Molybdenum (IV) sulphide... 

Barium sulphide has the usual dangerous reactions of sulphides (detonations with potassium chlorate and nitrate, combustion with phosphorus pentoxide). It catalyses the explosive combustion of dichlorine oxide. 

Lead peroxide is even more active than the oxide. It reacts violently with sulphur and sulphides. When it is ground up with sulphur, the mixture combusts. With hydrogen sulphide, the reaction is very exothermic and causes peroxide to incandesce and hydrogen sulphide to combust. Finally, it reacts violently with calcium, strontium and barium sulphides on heating. 

Barium carbonate is to be made by reacting sodium carbonate and barium sulphide. The quantities fed to the reaction agitators per 24 hours are 20 Mg of barium sulphide dissolved in 60 Mg of water, together with the theoretically necessary amount of sodium carbonate. 

The use of barium sulphide as a secondary sulphidizer [4] was examined on oxidized lead ores from Sicily (BaS). The results obtained were encouraging. Sulphidization using Na2S can also be improved with the use of ammonium salts (chloride and sulphate). These reagents are used in cases where the ore contains clay minerals and calcium carbonate, which prevents suphidization due to the production of soluble calcium bicarbonate. The ammonium increases the solubility of calcium carbonate and improves sulphidization. 

With Barium Sulphide.—In the previous process which was considered, steam was decomposed by means of spongy iron in the present process, instead of iron, barium sulphide is used. If steam is passed over barium sulphide heated to a bright red heat, the following reaction takes place —... 

The barium sulphate produced may be reduced by heating with coke to barium sulphide in accordance with the following equation —... 

The barium sulphide can be employed for the generation of fresh hydrogen and the carbon monoxide can be used for supplying a portion of the heat which is required for the process. 

G. Taddei7 prepared potassium iodide by adding a dil. soln. of potassium monosulphide to an alcoholic soln. of iodine. In place pf potassium sulphide, J. von Liebig and C. Wittstock used barium sulphide, prepared by calcining sulphate with coke. According to R. Schindler, the products obtained by the sulphide process are contaminated with sulphur compounds. G. S. Serullas treated potassium antimoniate (prepared by calcining tartar emetic) with an alcoholic soln. of iodine as long as the soln. was decolorized. The filtered soln. was evaporated to the point of crystallization. 

E. D.onath prepared a cone. aq. soln. by distilling ammonium chloride with a hot soln. of sodium sulphide until half the liquid has passed to the receiver. E. W. Parnell and J. Simpson patented a process for making ammonium sulphide by heating the mixed residues of the Leblanc and ammonia-soda processes they also used calcium or barium sulphide instead of the Leblanc residue. Ammonium carbonate with calcium or barium sulphide can also be used (NH COj-l-BaS =BaC03-t-(NH4)2S. According to J. Habermann, ammonium sulphide free from arsenic can be obtained only by using materials free from that element. 

Processing of Barium Sulphate into Barium Chloride, a. Preparation of Barium Sulphide. Mix 4 g of barium sulphate and 2 g of powdered charcoal, place the mixture into a chamotte or porcelain crucible, and cover the mixture with powdered charcoal. Close the crucible with its lid and roast it strongly (600-700 °C) for an hour in a muffle furnace. Write the equation of the reaction. 

Carbon disulphide may be estimated gravimetrically by treatment with baryta water (see p. 262), whereby barium sulphide is produced, which is then oxidised and weighed as sulphate.2... 

On allowing hydmrhlnrir aeid In lluw over barium sulphide, n unil orm niiTciil of liydm ieu sulphide should lie generaleil. 

Arsenic. — This is carried out as detailed under Barium Sulphide on page 72. 

Sulphates. Dissolve S gm. or potassium (lic.hroiiiate in 100 < <. (T water. uinl mid SO er. of hydrochloric. acid followod by 1 nrimii chloride solution. No jn-fM i litnU or barium sulphide sliould form on standing twelve hours. 

B. Laporte treated sodium phosphate with barium sulphide, etc. 3BaS+2NaOH +2 N a2HP0,1—B as P 04) 2 -J-3Na2 S -f-2 H2 0 and the washed barium phosphate is treated with sulphuric acid, etc. 

Potassium, sodium and calcium sulphides are applied externally to soften the skin by dissolving the epidermis in diseases such as psoriasis, acne and seborrhea. Mixtures of calcium or potassium polysulphides and thiosulphate behave similarly and are also depilatories. Another common hair remover is barium sulphide, mixed with starch or zinc oxide, whereas selenium suphide and cadmium sulphide are applied topically, in shampoos, to control dandruff. 

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