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Phosphorite, phosphate rock or rock phosphate is a non-detrital sedimentary rock that contains high amounts of phosphate minerals. The phosphate content of phosphorite (or grade of phosphate rock) varies greatly, from 4% [1] to 20% phosphorus pentoxide (P 2 O 5). Marketed phosphate rock is enriched ("beneficiated") to at least 28%, often more ...
Chemical formula. PO 3 ... In organic chemistry, phosphate or orthophosphate is an organophosphate, ... Rock phosphate can also be found in Egypt, ...
Phosphate is also used in animal feed supplements, food preservatives, anti-corrosion agents, cosmetics, fungicides, ceramics, water treatment and metallurgy. The production of fertilizer is the largest source responsible for minerals mined for their phosphate content.
Apatite is also found in clastic sedimentary rock as grains eroded out of the source rock. [7] [8] Phosphorite is a phosphate-rich sedimentary rock containing as much as 80% apatite, [9] which is present as cryptocrystalline masses referred to as collophane. [10] Economic quantities of apatite are also sometimes found in nepheline syenite or in ...
Phosphogypsum (PG) is the calcium sulfate hydrate formed as a by-product of the production of fertilizer, particularly phosphoric acid, from phosphate rock. It is mainly composed of gypsum (CaSO 4 ·2H 2 O).
The sites occupied solely by phosphate anions in stoichiometric hydroxyapatite, are occupied by phosphate or hydrogen phosphate, HPO 2− 4, anions. [14] These calcium-deficient phases can be prepared by precipitation from a mixture of calcium nitrate and diammonium phosphate with the desired Ca/P ratio, for example, to make a sample with a Ca ...
The term phosphate is also used in organic chemistry for the functional groups that result when one or more of the hydrogens are replaced by bonds to other groups. These acids, together with their salts and esters , include some of the best-known compounds of phosphorus, of high importance in biochemistry , mineralogy , agriculture , pharmacy ...
US production of phosphate rock peaked in 1980 at 54.4 million metric tons. The United States was the world's largest producer of phosphate rock from at least 1900, up until 2006, when US production was exceeded by that of China. In 2019, the US produced 10 percent of the world's phosphate rock. [91]