Muriate of Potash

Potassium Chloride 0-50-0-0

1. FEATURES

Muriate of Potash (MOP) is the common name for potassium chloride (KCl).

Potassium stimulates the growth of strong stems and gives the plant some disease resistance by promoting thickness of the outer cell walls. Adequate potassium can reduce moisture loss from growing plants, thereby giving some drought resistance. Potassium improves colour, flavour and storing quality of fruit and vegetables.

Potassium is present in all soils in reasonable quantities. In fact potassium is the seventh most abundant element in the Earth’s crust. At least 88% of the soil potassium is in the form of silicates, and so unavailable. The available forms leach readily, particularly in the higher rainfall areas & lighter soils. There are four commonly used Potassium fertilisers:

Potassium chloride, potassium sulphate, potassium nitrate and K-Mag all occur naturally in old sea or lake bed deposits. The potassium beds were formed by evaporation of these ancient seas and lakes and are often deeply buried by soil and rock.

The various layers deposited differ widely in composition from:

•          Rock salt, containing practically no potash

•          To carnalite, containing about 9% potash

•          To kainite, with 12 to 16% potash

•          Or sylvinite, from 16 to 17% potash

Other salt layers contain the salts of calcium, magnesium, etc and also a mixture of these materials. Before the potassium sources are used as fertilisers, extensive processing is necessary to remove impurities, especially common salt, NaCl.

There are many potassium ore deposits. One of the larger ones is in Saskatchewan, Canada, which is where Impact Fertilisers currently sources MOP. Australia uses about 300 000 tonnes of MOP per annum.

Brine sources can also be used to source potassium fertilisers e.g.The Dead Sea, Great Salt Lakes (USA).

MOP is the most concentrated form of granular K and typically the most cost effective form of K. The even granule size allows for accurate spreading. MOP is commonly blended with SSP to supply major nutrients for plants.

The practice of using “K” as the chemical symbol for potassium is from the German word for Potassium, Kalium.

2. TYPICAL ANALYSIS

3. PHYSICAL PROPERTIES

4. MANUFACTURE

Occurs as a natural salt and after processing to cleanse out unwanted salts, (especially common salt – NaCl) it is usually compacted into ‘chips’ and screened to meet size specifications.

5. USES

MOP is used extensively for fertilising pastures, fruit trees, vegetables, and other field crops.

6. STORAGE AND HANDLING

MOP stores well in bulk or in bags. It is not hygroscopic. MOP is particularly corrosive and so metal parts should be protected. After use, wash out equipment.

7. RESTRICTIONS

MOP should not be used on salt sensitive crops, where soil salt levels are high or increasing, or where irrigation water has high salt levels. Do not place MOP near seed unless seed has been protected by lime-coating or inoculation.

Do not store in silos.