Use
Potassium chloride (KCl), also known as muriate of
potash, is generally blended with other components to
make it a multinutrient fertilizer. It is a white crystalline
solid, available in fine, coarse and granular grades. It is
the least expensive carrier of potassium in the fertilizer
market. This important fertilizer contains about 48 to
52% plant food as potassium and about 48% chloride.
Coarser potassium blends well with granular N-P
compounds to form an NPK-blended multinutrient
fertilizer.
At least 78 % of the potassium salts are estimated to be
consumed worldwide, in the form of potassium chloride,
and over 90% of all processed potassium is used as
fertilizer. Muck, peat and sands are generally potassiumdeficient,
whereas arid soils are mostly potassium-rich,
with 448 kg/ha or more of readily available potassium.
Potassium chloride is neutral and totally watersoluble.
It can be applied to all soils and crops that are not
sensitive to chlorides. Soluble soil-potassium is adsorbed
and retained by soil colloids and thus prevented from
leaching. Roots take up potassium in the ionic form.
Potassium chloride is best applied either while sowing
or prior to it. However, when soils are light or coarsetextured,
the applied potassium may be lost through
leaching. So, it is preferable to apply potassium in split
doses. On heavy soils, the fertilizer is placed advantageously in bands, as in the case of phosphatic fertilizers.
Potassium chloride is manufactured from potash
minerals or brine. Sylvinite, which is a mixture of
potassium chloride and halite, is the major potash
mineral used for potassium chloride manufacture. A
large percentage of potassium chloride is mined and
refined either by the floatation or crystallization process.
Both processes, of which the floatation process is more
common, involve the separation of potassium chloride
from sodium chloride. Fine potassium chloride is a freeflowing
material which does not cake in dry places.