Calcium salts, purification sulfide

A. Dimethylprop-2-ynylsulfonium Bromide. A mixture of 6.2 g. (0.1 mole) of dimethyl sulfide (Note 1), 11.9 g. (0.1 mole) of 3-bromopropyne (Note 2), and 10 ml. of acetonitrile (Note 3) is stirred magnetically for 20 hours (Note 4) in a darkened 100-mi. round-bottomed flask (Note 6) fitted with a calcium chloride drying tube. The resulting white, crystalline mass is filtered with suction and washed with three 50-ml. portions of dry ether (Note 6) to give 16.4 g. (90%) of the sulfonium salt, m.p. 105-106°. This material may be used in the next step without purification but, if desired, it may be recrystallized from ethanol-ether (Note 7) with minimal loss to give a product melting at 109-110°. 

Leblanc s process, in its present form, consists of three distinct processes (1.) The conversion of Nad into the sulfate, by decomposition by HjS04. (3.) The conversion of the sulfate into carbonate, by heating a mixture of the sulfate with calcium carbonate and charcoal. The product of this reaction, known as. black ball soda, is a mixture of sodium carbonate, with charcoal and calcium sulfid and oxid. (3.) The purification of the product obtained in (3). The ball black is broken up, disintegrated by steam, and lixiviated. The solution on evaporation yields the soda salt or soda of commerce,... 

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