Potassium calcium sulphate

Woods contain from 0-2 to 4% of mineral ash. This consists largely of calcium, potassium and magnesium as carbonate, phosphate, silicate and sulphate. Aluminium, iron, sodium and chloride are also present. Sulphate contributes 1 to 10% by weight, usually 2 to 4%, and chloride 01 to 5%. 

Cameron, F.K. and Robinson, W.O. The solubility of calcium carbonate in aqueous solutions of potassium chloride and potassium sulphate at 25 °,J.Phys. Chem., ll(8) 577-580, 1907. 

Sulphate stock standard solution, 500 pg mM of SO -S - dissolve 2.717 g potassium sulphate (K SO ), previously dried at 105°C for 1 h and cooled in a desiccator, in calcium phosphate extractant, then transfer to a 1-1 volumetric flask with washings and make up to the mark with extractant. 

Paalme et al. (1990) studied the bulk deposition chemistry in the environment around the Estonian oil shale combustion area (Fig. 11 see also Kirso et al. 2002). Cations (i.e., calcium, potassium, sodium), anions (i.e., chloride, sulphate, nitrate), and - he x an e-e x t ractable PAHs were analysed in snow meltwater samples collected from 21 sampling stations in northeastern Estonia. It was found that the characteristic products of oil shale combustion, that is, Ca2+ and SC>4, accounted for over 92% of the major cations and 90% of the major anions in the snow. Correlation coefficients of r = 0.86 and 0.92 were noted for Ca2+ vs. SO - and Ca2+ vs. (SO2 - + 20 ), respectively. A high degree of correlation (r = 0.83) was also noted between Ca2+ vs. total PAHs in snow samples taken 150 km to the south of the thermal power plants. The deposition fluxes of Ca2+ and PAHs decreased with distance from the power plants. The average Ca2+ deposition flux 90 km... 

Lithium.—In order to extract lithium from the silicate minerals—petalite, lepidolite, spodumene, amblygonite, etc.—J. J. Berzelius 3 fused the finely powdered mineral with twice its weight of calcium or barium carbonate. L. Troost fused a mixture of finely powdered lepidolite with an equal weight of barium carbonate, half its weight of barium sulphate, and one-third its weight of potassium sulphate. In the latter case, two layers were formed lithium and potassium sulphates accumulated in the upper layer from which they were extracted by simple lixiviation. The sulphates are converted to chlorides by treatment with barium chloride. The filtered liquid is evaporated to dryness, and the chlorides extracted with a mixture of absolute alcohol, or pyridine. The lithium chloride dissolves, the other alkali chlorides remain as an almost insoluble residue. 

F. Kuhlmann obtained better results by increasing the press. The cost of the process renders the process unable to compete with the ammonia process. Patents have been obtained by G. Lunge (1866), W. Bramley (1886), and W. von Baranofi (1895) for modifications of this process. J. L. Smith prepared potassium carbonate by shaking for an hour a mixture of calcium carbonate with a soln. of potassium sulphate sat. with carbon dioxide. H. Jannasch also patented the preparation of potassium carbonate from kainite by treating potassium sulphate with witherite. 

The normal selenates of potassium, sodium, calcium and magnesium are very similar in properties to the corresponding sulphates, except that the potassium salt is much more soluble in water than potassium sulphate.3 Sodium selenate gives a decahydrate which effloresces, and the transition-point between this and the anhydrous salt is 31-8° C., above which point the solubility falls as the temperature rises. Calcium selenate gives a hemihydrate resembling plaster of Paris, and also a hydrate of composition CaSe04.l-5H2O.4... 

To 100 c.cs. ethyl alcohol in a -litre round-bottomed flask are carefully added with cooling 40 c.cs. cone, sulphuric acid. A reflux condenser is attached and the mixture heated for an hour on the water bath, and then allowed to cool. The liquid is poured into litre of water in a porcelain basin, and to this is added chalk, with stirring, until effervescence ceases. The calcium sulphate is filtered off, and washed with a little warm water. To the filtrate, which contains ethyl calcium sulphate, is added saturated potassium carbonate solution until the liquid gives a faint alkaline reaction to phenolphthalein. The calcium carbonate is filtered off and washed with a little hot water. The filtrate is then evaporated until crystallisation begins, when it is set aside to cool. The crystals of ethyl potassium sulphate are filtered off and dried, and a further crop obtained by concentrating the mother liquor. 

Sulphates. The amount of sulphate in wine, expressed as potassium sulphate, varies from 0-2 to o-6 gram per litre. This quantity may, however, be considerably increased as a result of plastering or addition of calcium sulphate during the fermentation of the must. 

Acrolein is prepared from glycerol by mixing the latter substance with twice its weight of powdered acid potassium sulphate, and after standing two days, distilling the mixture in a retort two layers collect in the receiver, the upper of which is acrolein. This aqueous distillate is shaken up with powdered litharge until no more lead sulphite is produced, and it is then distilled on a water-bath. The moist acrolein which collects, is allowed to stand over calcium chloride for two hours and then redistilled. B.p. 52°. Yield, about 35 per cent. 

Sodium chloride Sodium bromide Sodium iodide Sodium sulphate Sodium silicate Potassium sulphate Lithium chloride Calcium carbonate Calcium sulphate Magnesium sulphate Manganous carbonate Ferrous carbonate. Aluminium phosphate Ammonium nitrate Organic matter... 

Potassium Phosphates.—Basic or neutral phosphates (Rhenania phosphates) may be made directly from rock phosphate by mixing it with potassium chloride, some form of carbon and soda, and heating to over 1000° C. in an electric furnace.2 One of these products has the composition Ca2KNaP208, with some silica. Such products may contain 23 to 31 per cent, of soluble phosphoric acid. Potassium superphosphate has been made by mixing potassium sulphate and calcium carbonate with concentrated phosphoric acid in a lead-lined vessel.3 The CaS04.2Ha0 is separated and the filter-pressed solution is evaporated to dryness by steam heat. The residue may be treated with more phosphoric acid and again evaporated. The reaction is expressed by the equation... 

Portland cement clinkers contain small amounts of alkalis and sulphates derived from the raw materials and fuel. Both alkalis and SO3 can be present in the major clinker phases, but tend to combine preferentially with each other to form alkali or potassium calcium sulphates, and it is necessary to consider these components together. In addition, silicate and aluminate phases containing sulphate can form either as intermediates or in undesirable deposits in eement making, and a calcium aluminate sulphate is a major constituent of some expansive and other speeial cements. 

The anhydrous sulphate is a constituent of oceanic salt deposits, and is called thenardite. An isomorphous mixture with potassium sulphate is known as glaserite a double salt with magnesium sulphate as astrakanite, and with calcium sulphate as glauberite. 

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