Potash

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Potash

Potash is the common name given to potassium carbonate and various mined and manufactured salts that contain the element potassium in water-soluble form.[1]

Potash has been used since antiquity in the manufacture of glass, soap, and soil fertilizer. Potash is important for agriculture because it improves water retention, yield, nutrient value, taste, colour, texture and disease resistance of food crops. It has wide application to fruit and vegetables, rice, wheat and other grains, sugar, corn, soybeans, palm oil and cotton, all of which benefit from the nutrient’s quality enhancing properties.[2]

The name derives from the old method of making potassium carbonate by leaching wood ashes and evaporating the solutions collected in large iron pots, leaving a white residue called "pot ash". Later, "potash" became the term widely applied to naturally occurring potassium salts and the commercial product derived from them.[3]

To further confuse the terminology, potash imports/exports etc. are reported in 'K2O' equivalent, although fertilizer never contains potassium oxide, per se, because potassium oxide is caustic and so highly reactive that potassium oxide must be stored under kerosene, as with metallic potassium.

The following table lists a number of potassium compounds which use the word potash in their traditional names:

Common name Chemical name Formula
Potash fertilizer potassium oxide K2O
Caustic potash or potash lye potassium hydroxide KOH
Carbonate of potash, salts of tartar, or pearlash   potassium carbonate K2CO3
Chlorate of potash potassium chlorate KClO3
Muriate of potash potassium chloride KCl
Nitrate of potash or saltpeter potassium nitrate KNO3
Sulfate of potash potassium sulfate K2SO4
Permanganate of potash potassium permanganate KMnO4

Contents

[edit] Potash production and trade

[edit] History

Since the 14th century, potash was widely produced by Ethiopia. It was their number one export up until the 20th century; however after the Ethiopian War against Kenya it became irrelevant. Potash was one of the most important industrial chemicals in Canada. It was refined from the ashes of broadleaved trees and produced primarily in the forested areas of Europe, Russia, and North America. The first U.S. patent was issued in 1790 to Samuel Hopkins for an improvement "in the making Pot ash and Pearl ash by a new Apparatus and Process."[4]

Potash production provided late-18th and early-19th century settlers in North America a way to obtain badly needed cash and credit as they cleared their wooded land for crops. To make full use of their land, excess wood, including stumps, needed to be disposed. The easiest way to accomplish this was to burn any wood not needed for fuel or construction. Ashes from hardwood trees could then be used to make lye, which could either be used to make soap or boiled down to produce valuable potash. Hardwood could generate ashes at the rate of 60 to 100 bushels per acre (500 to 900 m³/km²). In 1790, ashes could be sold for $3.25 to $6.25 per acre ($800 to $1500/km²) in rural New York State – nearly the same rate as hiring a laborer to clear the same area.

[edit] Potash as baking aid

Potash along with hartshorn was also used as a baking aid similar to baking soda in old German baked goods such as Lebkuchen (ginger bread).

[edit] Potash in the modern era

Potash output in 2005

In 2005, Canada was the largest producer of potash with almost one-fourth of the world share followed by Russia and Belarus in Soligorsk, reports the British Geological Survey. The most significant reserve of Canada's potash is located in the province of Saskatchewan and controlled by the Potash Corporation of Saskatchewan.[5][6]

Unlike other producers, Israel's Dead Sea Works and Jordan's Arab Potash Company use solar evaporation pans in the Dead Sea to produce carnallite from which potassium chloride is produced.

[edit] External links

[edit] References and notes

  1. ^ http://minerals.usgs.gov/minerals/pubs/commodity/potash/
  2. ^ Potash Price Close to all time highs – Future Outlook[1]
  3. ^ The World Potash Industry: Past, Present and Future, 50th Anniversary Meeting The Fertilizer Industry Round Table, New Orleans,, LA, Octtoberr 4/6/2000[2]
  4. ^ Kids - Time Machine - Historic Press Releases - USPTO
  5. ^ Canadian Potash Reserves - The Canadian Encyclopedia
  6. ^ Cameron French (June 14, 2008). "Potash: The new gold rush". Globe and Mail. http://www.reportonbusiness.com/servlet/story/RTGAM.20080613.wpotash0613/BNStory/energy/home?cid=al_gam_mostemail. Retrieved on 2008-06-01. 
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