Fused Calcium Magnesium Phosphate

Fused Calcium Magnesium Phosphate. In a process developed by TVA, a mixture of phosphate rock and olivine or serpentine (magnesium silicate) is fused in an electric furnace.21 The molten product is quenched with water and used in a finely divided state as a fertilizer. The product, a calcium magnesium phosphate (CMP) glass, contains about 20 percent P205 and 15 percent MgO. Over 90 percent of the product is soluble in citric acid. 

Controlled-Release Phosphate Fertilizers. Several controlled-release phosphates have been produced commercially. Important among them are ground phosphate rock, basic slag, and fused calcium magnesium phosphate. These products have been discussed earlier. 

The company has 1300 employees. Major products are PP resin, fused calcium magnesium phosphate, mixed and compound fertilizer. Its annual PP output is 11 500 tonnes. 

Derivation Finely ground ore is leached under oxidizing conditions to give uranyl nitrate solution. The uranyl nitrate, purified by solvent extraction (ether, alkyl phosphate esters), is then reduced with hydrogen to uranium dioxide. This is treated with hydrogen fluoride to obtain uranium tetrafluoride, followed by either electrolysis in fused salts or by reduction with calcium or magnesium. Uranium can also be recovered from phosphate sand. 

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