Potassium economic importance

Scrap that is unsuitable for recycling into products by the primary aluminum producers is used in the secondary aluminum industry for castings that have modest property requirements. Oxide formation and dross buildup are encountered in the secondary aluminum industry, and fluxes are employed to assist in the collection of dross and removal of inclusions and gas. Such fluxes are usually mixtures of sodium and potassium chlorides. Fumes and residues from these fluxes and treatment of dross are problems of environmental and economic importance, and efforts are made to reclaim both flux and metal values in the dross. 

Most abundant group of materials, composed of silicates of aluminium with sodium, potassium, calcium, and rarely barium. Most economically important mineral. Used for ceramics, glass, abrasive wheels, cements, insulation and fertilizer. 

Economic Importance. The worldwide production of magnesium sulfate products including potassium magnesium sulfate (fertilizer) was 3.4 10 t/a in the mid-1970 s of which 2.3 10 t was kieserite MgS04 H2O (a byproduct of the potash industry). The main producer countries are the USA and the Federal Republic of Germany. The USA consumption in 1996 excluding natural kieserite was 57-10 t. 

The economic importance of potassium stems in large part from its role as a plant nutrient. Enormous quantities of potassium chloride from underground deposits are used as fatilizer to increase the world s food supply. In fact, plants wctc an early source of potassium compounds. Wood and otho- plant materials were burned in pots to give ashes (potash) that consist primarily of potassium carbonate, from which otha-potassium compounds could be manufactured. The name potassium has its origin in the word potash from this earlier source of the element. 

Economic Aspects. Tables 11 and 12 illustrate the relative importance of the various grades of potassium chloride in the U.S. domestic... 

In the United States, aluminum sulfate is usually produced by the reaction of bauxite or clay (qv) with sulfuric acid (see Sulfuric acid and sulfur trioxide). Bauxite is imported and more expensive than local clay, generally kaolin, which is more often used. Clay is first roasted to remove organics and break down the crystalline stmcture in order to make it more reactive. This is an energy intensive process. The purity of the starting clay or bauxite ore, especially the iron and potassium contents, are reflected in the assay of the final product. Thus the selection of the raw material is governed by the overall economics of producing a satisfying product. 

The alkali metals are not found free in nature, because they are so easily oxidized. They are most economically produced by electrolysis of their molten salts. Sodium (2.6% abundance by mass) and potassium (2.4% abundance) are very common in the earth s crust. The other lA metals are quite rare. Francium consists only of short-lived radioactive isotopes formed by alpha-particle emission from actinium (Section 26-4). Both potassium and cesium also have natural radioisotopes. Potassium-40 is important in the potassium-argon radioactive decay method of dating ancient objects (Section 26-12). The properties of the alkali metals vary regularly as the group is descended (Table 23-1). 

Compotmds of potassium are economically more important than the metal. KCl is used extensively in fertihzers. KOH is used to make hquid soaps and detergents. Potassium nitrate, KNO3, serves primarily as an oxidizing agent in gunpowder and pyrotechnics. Potassium superoxide, KO2, is used in backup ventilation equipment as it generates oxygen gas in the presence of CO2. Potassium ions are essential to plants and animals as many metabolic reactions and pathways depend on their presence, see also Alkali Metals. 

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