Langbeinite

Certain minerals, however, such as sylvite, carnallite, langbeinite, and polyhalite are found in ancientlake and sea beds and form rather extensive deposits from which potassium and its salts can readily be obtained. Potash is mined in Germany, New Mexico, California, Utah, and elsewhere. Large deposits of potash, found at a depth of some 3000 ft in Saskatchewan, promise to be important in coming years. 

Potassium Sulfate. Potassium sulfate is a preferred form of potash for crops that have a low tolerance for chloride. Tobacco and potatoes ate two such crops. K2SO4 is produced most often from langbeinite by metathetical reaction in aqueous solution ... 

Langbeinite, also commercially called Sul-Po-Mag and K-Mag, is also used directly as a fertilizer. Beneficiated langbeinite contains 22% K2O and 18%... 

The common ores of potassium iaclude (/) sylvinite, a mixture of sylvite, KCl, and halite (2) hartsalz, composed of sylvite, haUte, and kieserite [14567-64-7] MgSO 2 anhydrite 5) camaUitite, camaUite [1318-27-0] KCl. MgCl 6H20, and halite (4) langbeinite ore, langbeinite,... 

In contrast to sodium chloride, langbeinite has an extremely slow rate of solution. Upon control of agitation time, essentially all the sodium chloride dissolves but most of the langbeinite remains as a soHd. Langbeinite is separated from the brine, dried, and then screened into granular, standard, and special-standard particle sizes. These fractions are marketed directiy. In one plant, the unsalable fines are used as the source of sulfate reactant for the production of potassium sulfate. 

Kieserite is not present in U.S. potassium salt deposits in commercial quantities. Langbeinite is the predominant U.S. magnesium sulfate salt. The latter, a raw material for the production of potassium sulfate in New Mexico, reacts directiy with potassium chloride ... 

The value of langbeinite as a fertilizer is enhanced because, in pure form, it contains 18.8 wt % potassium, 11.7 wt % magnesium, and 23.0 wt % sulfur. AH three elements are essential nutrients for plant growth. Commercial grades contain ca 97 wt % mineral the remaining 3 wt % consists of water-insoluble clays and residual sodium chloride. 

Chemical fertiliser is the predominant market for langbeinite. Comparatively small but increasing amounts of langbeinite are used by the animal feed ingredient industry (see Feeds and feed additives). Producers who supply this market must take special precautions to be sure that any langbeinite intended as an animal feed ingredient meets all USDA specifications for toxic heavy metals and other impurities. 

Potassium sulfate and langbeinite may be screened into three different size ranges to serve all segments of the fertilizer industry. Typical screen analyses of the size products are presented in Table 14. Chemical analyses for the products are shown in Table 15. 

Table 14. Typical Screen Analyses of Potassium Sulfate and Langbeinite ...

Sodium, 22 700 ppm (2.27%) is the seventh most abundant element in crustal rocks and the fifth most abundant metal, after Al, Fe, Ca and Mg. Potassium (18 400 ppm) is the next most abundant element after sodium. Vast deposits of both Na and K salts occur in relatively pure form on all continents as a result of evaporation of ancient seas, and this process still continues today in the Great Salt Lake (Utah), the Dead Sea and elsewhere. Sodium occurs as rock-salt (NaCl) and as the carbonate (trona), nitrate (saltpetre), sulfate (mirabilite), borate (borax, kemite), etc. Potassium occurs principally as the simple chloride (sylvite), as the double chloride KCl.MgCl2.6H2O (camallite) and the anhydrous sulfate K2Mg2(S04)3 (langbeinite). There are also unlimited supplies of NaCl in natural brines and oceanic waters ( 30kgm ). Thus, it has been calculated that rock-salt equivalent to the NaCl in the oceans of the world would occupy... 

KCl-langbeinite ore, 20 628. See also Potassium chloride KDF continuous pressure filter,... 

Procedure, for reducing sugars, 23 475 Laneth-5, cosmetic surfactant, 7 834t Langbeinite, 5 785t 20 627, 628 in chemical fertilizer, 20 629 screen analyses of, 20 629t Langelier saturation index (LSI), 26 142— 143... 

Potassium chloride, 11 122 12 67 20 611-625. See also KCl-langbeinite ore chemical grades of, 20 62It compaction of, 20 621-625 corrosive effect on iron, 7 806 electrolysis of, 20 633 encapsulated, 16 453 froth flotation of, 20 615-616 mining, 20 613-615 refining, 20 615-621 as salt substitute, 22 819-820 separation from sodium chloride, 20 622 therapeutant for aquaculture in U.S.,... 

Potassium chloride is produced by several processes. The salt is recovered from natural brine by solar evaporation in shallow ponds. Various methods are employed in mining ores from their natural deposits. Usually it is recovered from sylvinite or a naturally occuring complex mixture of langbeinite and kainite. 

Potassium and sodium sulfates and their double sulfates with calcium and magnesium occur naturally in various salt lakes. Potassium sulfate also occurs in certain volcanic lava. Its double salt with magnesium occurs in nature, as the mineral langbeinite. 

The salt may be obtained from its naturally occurring mineral, langbeinite, K2S04 2MgS04. The ore first is crushed and washed with water to separate sodium chloride. After that, magnetite is separated from the washed langbeinite by magnetic separation. After the separation of these two major impurities, the purified double salt is treated with an aqueous solution of potassium chloride to obtain potassium sulfate ... 

Langbeinite. Krugite. Vanthoffite. Lowito. Anhydrite (or karstcnite). Gypsum. ... 

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