34 Preparation of i:substances 



feldspar is unlimited, but here again the 

 cost of production is so great that little 

 potash is, as yet, produced from this source. 

 Another mineral containing large quantities 

 of potash is found in Utah and called alunite. 

 This substance contains silicates and sul- 

 fates of potassium and aluminium which on 

 heating furnish water soluble sulfate of pot- 

 ash. Six hundred tons a month of potas- 

 sium sulfate were being produced in 1918 

 from this source. 



Potash is being produced in this country, 

 England and France from the blast furnaces 

 of the steel industry. The limestone, iron ore, 

 and coke used in the smelting may each con- 

 tain some potash; if so during the heating 

 some of this is volatilized. Special devices, 

 electrical precipitators, take the potash-bear- 

 ing dust out of the gases as they pass from the 

 furnaces. Potassium chlorid is the substance 

 obtaind. As there is generally insufficient 

 chlorin to combine with the potassium the 

 amount of substance volatilized is limited by 

 the chlorin available. The addition of com- 

 mon salt, sodium chlorid, to the furnace 

 charge consequently increases the amount 

 of potash recoverd. It is said that there is 

 sufficient potash available from this source to 

 furnish the entire needs of this country. 



The cement kilns also volatilize potassium 



