zeolite

Click a letter for the index

Or search the encyclopaedia:

 

 

Go

 

Any of the hydrous aluminium silicates, also containing sodium, calcium, barium, strontium, or potassium, chiefly found in igneous rocks and characterized by a ready loss or gain of water. Zeolites are used as ‘molecular sieves’ to separate mixtures because they are capable of selective absorption. They have a high ion-exchange capacity and can be used to separate petrol, benzene, and toluene from low-grade raw materials, such as coal and methanol.

Green stands for agriculture. Red recalls the struggle for independence. White denotes peace. Yellow symbolizes mineral wealth. Effective date: April 1983. >>