Sodium stannate

HjSnCl, with which the aniline forms a salt, aniline chlorostannate (C4HjNH )i,H SnCl4, similar in type to aniline chloroplatinate (p. 448). The crude product is therefore made strongly alkaline with sodium hydroxide, which liberates the base with the formation of sodium stannate, and the aniline can (C4H NH,),H,SnCl, + SNaOH = 2C,H,NH, + Na.SnO, +6NaCl + sHjO then be removed by steam-distillation. 

The niter and fresh caustic soda, required to maintain the fluidity of the salt bath in the reactor chamber, are added gradually. When the color of the saturated salts turns from a dark gray to white, the impurity metals are at their highest state of oxidation, and the lead content of the spent salts is very low. In a modification, the arsenic and tin are selectively removed as sodium arsenate and sodium stannate, followed by the removal of antimony as sodium antimonate. 

Hydrated Stannic Oxide. Hydrated stannic oxide of variable water content is obtained by the hydrolysis of stannates. Acidification of a sodium stannate solution precipitates the hydrate as a flocculent white mass. The colloidal solution, which is obtained by washing the mass free of water-soluble ions and peptization with potassium hydroxide, is stable below 50°C and forms the basis for the patented Tin Sol process for replenishing tin in staimate tin-plating baths. A similar type of solution (Staimasol A and B) is prepared by the direct electrolysis of concentrated potassium staimate solutions (26). 

Potassium staimate, K2Sn(OH) (mol wt 298.93), and sodium stannate [12058-66-17, Na2Sn(OH), mol wt 266.71, are colorless crystals and are soluble in water. The solubiUty of potassium stannate in water is 110.5 g/100 mL water at 15°C and that of sodium stannate is 61.5 g/100 mL water at 15°C. The solubihty of sodium stannate decreases with increasing temperature, whereas the solubiUty of potassium stannate increases with increasing temperature. The solubihty of either sodium or potassium stannate decreases as the concentration of the respective free caustic increases. Hydrolysis of stannates yields hydrated stannic oxides and is the basis of the Tin Sol solution, which is used to replenish tin in stannate tin-plating baths (28,29). 

Zinnozyd, n. tin oxide, specif, stannic oxide, tin(IV) oxide, -chlorid, n. stannic chloride, tin(IV) chloride, -hydrat, n. stannic hydroxide, tin(IV) hydroxide, -natron, n. sodium stannate. -salz, n. stannic salt, tin(IV) salt. 

Zion-saum, m. list of tin, selvedge, -allure, /. stannic acid, -saureonhydrid, n. stannic anhydride, tin dioxide, -schlich, m. (Ores) tin slimes, fine tin. -schrei, m. = 2Unngeschrei. -seife, /. (Mining) stream tin. -soda, /. sodium stannate. -staub, m. tin dust, -stein, m. tinstone, cassiterite. -sulfid, n. tin sulfide, specif, stannic sulfide, tin(IV) sulfide. -BuUocyanid, 1. tin thiocyanate, specif. 

Articles of steel, copper or brass which require a thicker coating than is possible by chemical replacement, and which are difficult to tin by normal electrodeposition, may be coated by immersion in alkaline sodium stannate solution in contact with aluminium suitably placed to act as anode. 

Tin-zinc alloys of a wide range of composition can be electrodeposited from sodium stannate/zinc cyanide baths only the coatings with 20-25% zinc have commercial importance . 

Perkin described a FR treatment for cotton using a mixture of sodium stannate and ammonium sulfate. 1912... 

Sodium silicide, 22 765 Sodium stannate, 24 806 Sodium stearate... 

Compounds Stannic oxide tin tetrachloride stannic chloride stannous chloride stannous sulfate sodium stannate potassium stannate... 

Sodium Stannovanadates or Vanadostannates.—By crystallising mixed solutions of sodium stannate and sodium orthovanadate, a series of sodium stannovanadates has been prepared, the salts having the following compositions —... 

A basic stannic pyroarsenate, SnAs2O7.SnO3.10H2O, is obtained when the white gelatinous precipitate formed by boiling a solution containing sodium stannate, excess of sodium orthoarsenate and nitric acid, is dried at the ordinary temperature.4 The salt becomes anhydrous at 120Q C. 

Of the large volume of tin compounds reported in the literature, possibly only ca 100 are commercially important. The most commercially significant inorganic compounds include stannic chloride, stannic oxide, potassium stannate, sodium stannate, stannous chloride, stannous fluoride, stannous fluoroborate, stannous oxide, stannous pyrophosphate, stannous sulfate, stannous 2-ethylhexanoate, and stannous oxalate. Also important are organotins of the dimethyl tin, dibutyltin, tributyltin, dioctyltin, triphenyltin, and tricyclohexyltin families. 

The reactants tin(IV) chloride, alkali-metal base, and colloidal silica (Ludox-HS40) were thoroughly mixed at room temperature, according to the ratios 2-5M20 Sn02 4-10SiO2 8O-IOOH2O, for each synthesis [47], Cabosil (fumed silica) and sodium stannate were also used as reactants. 

Because these fire-retardant salts are water-soluble and subject to leaching, several new methods have been developed which provide a water-resistant or permanent treatment for cotton fabrics and cellu-losic materials. Perkin developed a process involving successive treatment with sodium stannate and ammonium sulfate, which precipitates stannic oxide in the cellulose libers. Antimony oxide in combination with vinyl chloride or other chlorinated polymers has also been found effective. A more recent approach to this problem involves application of fire-retardant resin-forming or cross-linking compounds. " These include materials and methods based on the copolymerization of tetrakis(hydroxymethyl)phosphonium chloride and methylol — melamine, the reaction of bromoform and triallyl phosphate to form a cross-linked polymer, and the cross-linking reaction of tris(l-aziridinyl)phosphine oxide with cellulose, or its copolymerization with tetrakis(hydroxymethyl)phosphonium chloride and other materials. ... 

Salts Compounds formed by the union of acids and bases, by the action of alkalies upon metals, or by the direct union of elements. The term is often incorporated in the common name of salts used as pharmaceuticals bitter salts, epsom salt, or Seidlitz salt (magnesium sulfate), preparing salt (sodium stannate), Preston s salts (ammonium chloride), Rochelle salt or Seignette s salt (potassium and ammonium tartrate), salt of Mars (ferrous sulfate), salt of Saturn (lead acetate), salt of tartar (potassium carbonate), salt of tin (stannous chloride), salt of wisdom (mercury bichloride and ammonium chloride), sore-throat salt (fused potassium nitrate), vinegar salts (calcium acetate), and vomiting salt (zinc sulfate). The term is also applied to some acids, such as salt of lemon or sour salt (citric acid), salt of sorrel (oxalic acid), and spirit of salt (muriatic acid). ... 

The use of tin involves a number of difficulties. The chlorides of tin produced in the presence of an excess of hydrochloric acid give chlorostannic acid, which combines with aniline and some other arylamines to form complex double salts as shown in equation (4). In order to decompose these salts alkali is used. A great excess must be employed in order to change the stannic hydroxide, which i,s formed, to soluble sodium stannate ... 

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