Alkali bicarbonates iodides

Potassium iodide can also be obtained from the aq. extract of kelp or from the mother liquid remaining after the separation of sodium chloride and potassium sulphate from sea-water by evaporation. In E. Allary and J. Pellieux process,8 the liquid is evaporated to dryness and roasted in a special furnace so as to avoid a loss of iodine. The product is fractionally extracted with cold water, when a soln. is obtained which on evaporation gives a residue with 50 per cent, of alkali iodide. This product is extracted.in a special digester with 50 per cent, alcohol. The solvent dissolves little more than the iodides. The alcohol is distilled off, and on evaporation a residue containing about 34 per cent, of potassium iodide, and 66 per cent, of sodium iodide is obtained. To convert the latter into potassium iodide, the proper quantity of a soln. of potassium carbonate is added and carbon dioxide passed into the liquid whereby sodium bicarbonate is precipitated. The precipitate is separated by a filter press, and the small amount of sodium bicarbonate remaining in the soln. is separated by the addition of a little hydrochloric acid and the sodium chloride and potassium iodide separated by fractional crystallization. In E. Sonstadt s process, the mother liquid is treated with chlorine mixed with potassium chlorate or permanganate so as to convert the iodine into iodate. A soln. of a barium salt is added, and the barium iodate treated with potassium sulphate. Barium sulphate is precipitated, and the soln. of potassium iodate is evaporated to dryness and calcined to convert the iodate to iodide. The latter is purified by crystallization. 

This is the reverse of the reaction discussed above, and for the reaction to run completely in this direction the hydrogen iodide must be neutralised as fast as it is formed. An alkali cannot be added as it would react with the iodine, but the hydrogen iodide may be safely neutralised with sodium bicarbonate ... 

Detn of acet based on the addn to a soln contg sample K iodide and Na hypochlorite in the presence of alkali, until the 1st appearance of free iodine, which may be detected by starch-bicarbonate indicator)... 

Incompat Acids, alkalies, alum, ammonia water, amyl nitrite benzoates betanaphthol, phenol, calomel, chloral hydrate, copper sulfate, ferric chloride ferrous sulfate chromium trioxide (chromic acid), cinchona alkaloids, hydrocyanic acid iodides iodine Lead subacetate mercuric chloride, orthoform potassium permanganate, resorcinol, sod. bicarbonate sod. salicylate (in powder) soln arsenic and mercury iodide, spirit nitrous ether (unless prescribed with sod, bicarbonate), syrup ferrous iodide, tartar emetic tannic acid, thymol, urethane, infusions of catechu, cinchona, rose leaves and uva ursi tinctures of catechu, ferric chloride, cinchona, hamanielis iodine, kino, and rhubarb. 

Pharmaceutical Incompat, (from Remington s Pharmaceutical Sciences) Aspirin forms a damp to pasty mass when triturated with acetanilide, phenacetin, antipyrine, amidopyrine, methenamine, phenol or phenyl salicylate. Powders containing aspirin with an alkali salt such as sodium bicarbonate become gummy on contact with atmospheric moisture. Hydrolysis oecnrs in admixture with salts contg water of crystallization. Solns of the alkaline acetates and citrates, as well as alkalies themselves, dissolve aspirin but the result -ing solns hydrolyze rapidly to form salts of acetic and salicylic acids. Sugar and glycerol have been shown to hinder this decompn. Aspirin very slowly liberates hydriodic acid from potassium or sodium iodide. Subsequent oxidation by air produces free iodine. 

Incompatibility of all strychnine salts alkalies, alkali carbonates and bicarbonates, benzoates, dichromates, bromides, iodides, tannic and picric acids, salicylates, borax, gold chloride and other alkaloid precipitants, piperazine, potassium -mercuric iodide (riot if acacia is present). 

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