Potash, Bicarbonate Carbonate

Dry residue (solid residue) is a characteristic of soil salinity, it is determined by the ratio of anions and catiorts in the soil solution. In normal conditions it can t exceed 0.30%, in soil samples it is equal to 0.35%. Salinity is determined by salt content in soil solution. Salts ate need to be formed mostly sodiiun, calcium and magnesium cations with chloric and sirlfuric anions. Potash cations, bicarbonate, carbonate and nitrate anions can make insignificarrt part. Thrrs results by dry residue in soil, which were obtained in this experiment, allow drawing conclusion that anion and cation amount is optimal and they are the main compotrrtds of the soil in cirrrerrt agroclimatic conditions. 

North American Chemical Co. produces borax pentahydrate and decahydrate from Seades Lake brines in both Trona and West End, California (see Chemicals frombrines). The 88 km dry lake consists of two brine layers, the analyses of which are given in Table 11. Two distinct procedures are used for the processing of upper and lower lake brines. Borax is produced in Trona from upper lake brines by an evaporative procedure involving the crystallization of potash and several other salts prior to borax crystallization as the pentahydrate (104). A carbonation process is used in West End, California to derive borate values from lower lake brines (105). Raw lower stmcture brine is carbonated to produce sodium bicarbonate, which is calcined and recrystallized as sodium carbonate monohydrate. The borate-rich filtrate is neutralized with lake brine and refrigerated to crystallize borax. 

Potassium carbonate is produced most conveniently by passing carbon dioxide into an aqueous solution of caustic potash, evaporating the solution to obtain the bicarbonate, and heating the bicarbonate ... 

Chemically pure carbonate of potash is best prepared by the ignition of pure bicarbonate (see below) in iron or (better) in silver or platinum vessels or else by the calcination of pure bitartrate (see TABTaaic Acu>). The iatlec operation furnishes an intimate mixture of the carbonate with charcoal, from which tho carbonate ia extracted by lixiviation with water and filtration. The filtrate is evaporated to dryness (in iron or platinum) and the residue fully dehydrated by gentle ignition. Tho salt is thus obtained as a white porous mass, fusible at a red heat (836 C., Carndlcy) into a colourless liquid, which freezes into a while opaque piass. The dry salt ia very hygroscopic it deliquesces into an oily solution oleum tartar ) in ordinary air. 100 parts of water dissolve—... 

Bicarbonate of potash, KO, CO, -f 2 aq., is obtained by exposing a strong solution of the carbonate to a current of carbonic acid, or to the atmosphere of a fermenting vat, when the bicarbonate is deposited in crystals. The purest carbonate is obtained by igniting these crystals. 

Carbonate of Magnesia, Mg 0, Co, occurs as a rock in the East Indies. When a solution of bicarbonate is exposed to the air, crystals are deposited, which are MgO, CO,-(-3 aq. Other crystals have been obtained, which were Mg, O, C O - -5 aq. When carbonate of potash is added to a solution of sulpWe of magnesia, a precipitate falls, which contains 4 Mg 0-1-3 C 0, +4aq. 

Casein powder is not very soluble in pure water, but dissolves better in an alkahne medium, produced by adding potassium or sodium bicarbonate or carbonate, or possibly potash. The normal dose is from 10 to 20 g/hl, although in curative treatment 50 g/hl or more may be used. Casein powder s preventive action is not fully understood, but it affects phenols, either by eliminating them or, more probably, by protecting them from oxidation. 

When carbonieanhydridehas passed through the carbonate of potash solution for two minutes, so as to expel the whole of the air of the apparatus, fix the cork tightly in the neck of the bottle, and let the process go on for a week. At the end of this time numerous crystals of bicarbonate of potash will have formed, which are to be removed, shaken with twice their bulk of cold distilled water, and, after decantation of the water, drained, and dried on filtering paper by exposure to the air. The mother-liquor, filtered if necessary, and concentrated to one half, at a temperature not exceeding 110° F., will yield more crystals. The tube immersed in the solution of carbonate of potash, which should have as large a diameter as possible, may require the occasional removal of the crystals formed within it, in order that the process may not be interrupted. 

The weights of fixed air contained in 1000 parts of the alkalis and marble were found to be marble 407, 408 (440) volatile sal ammoniac (carbonate of ammonia a special apparatus was used with this) 528, 533 (559 3 2(NH4)20, 3CO2) pearl ash 284, 287 (318) bicarbonate of potash 423... 

Cavendish described (Expt. XV) the preparation of bicarbonate of potash by shaking a solution of the carbonate (pearl ash) in a bottle to the neck of which was attached a bladder filled with fixed air. The crystals obtained were not deliquescent and dissolved in about 4 times their weight of water at room temperature. Cavendish mentions Black s statement that on exposing a solution of salt of tartar (potassium carbonate) to the air for a long time, crystals separated which seemed to be composed only of the alkali, and of a larger quantity of air than is usually contained in that salt . ... 

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