Muriate of Potash potassium chloride (KCl), a refined red or greyish red, cubic, crystalline compound that closely resembles common salt (sodium chloride). For agricultural use potassium chloride is often called Muriate of Potash. The name 'Muriate' is derived from the term muriatic acid, which is a common name for hydrochloric acid. Over 90 percent of all processed potassium (K) is consumed as fertiliser and at least 78 percent of the K-salts consumed worldwide is Muriate of Potash. It may contain 48 to 62.5% K20 (39 to 61% K), and about 47% chlorine.

Commercial production of K-fertilisers, mainly Muriate of Potash, began in Germany in 1861. Later, Liebig found that K is an essential element for plant growth. Underground K-salt deposits are the major source for K-fertiliser. Potassium chloride is the predominant K-salt in most K deposits.

Continuous mining of the boring or rotating type is commonly used to extract ore, composed of the chloride salts. Muriate of potash is manufactured through refining techniques. Flotation and crystallisation are two processes used for the purification of KCl from potash ores. Both processes involve a separation of KCl from NaCl. Crystals of these two chemicals are commonly found interlocked in a mineral mixture called sylvinite. The flotation process is by far the most prevalent, and this process produces the greatest proportion of the agricultural Muriate of Potash.

Potassium fertiliser as Muriate of Potash added to the soil is 100 percent water- soluble. It is suitable for most of the crops except sugarcane, sugar beet, potato and tobacco. Annual consumption of Muriate of Potash in Bangladesh is around 150 thousand tons, all of it imported from abroad. [Md Akhter Hossain Khan]