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Related to superphosphate: bone meal, Triple superphosphate



superphosphate of lime,

Ca(H2PO4)2, is a compound produced by treating rock phosphate with sulfuric acid or phosphoric acid, or a mixture of the two. It is the principal carrier of phosphate, the form of phosphorus usable by plants, and is one of the world's most important fertilizers. Ordinary superphosphate contains about 20% available phosphate; double superphosphate (also called treble superphosphate) contains 40%–50% available phosphate.



the most widely used mineral phosphorus fertilizer. The phosphorus in superphosphate is usually in the form of monocalcium phosphate and free phosphoric acid. The fertilizer contains gypsum and other admixtures, such as iron and aluminum phosphates, silica, and fluorine compounds. Superphosphate is obtained by the treatment of natural phosphates—apatite or phosphorite—or an apatite concentrate with sulfuric acid according to the reaction

Ca3(PO4)2 + 2H2SO4 = Ca(H2PO4)2 + 2CaSO4

Double superphosphate is derived by treating apatite or phosphorite with phosphoric acid.

Several types of superphosphate are produced industrially in the USSR. Ordinary superphosphate is a gray powder that is virtually noncaking and of average drillability; in fertilizer it provides 14–19 percent P2O5 that is available to plants. Granular superphosphate is derived from powdered superphosphate by adding moisture to it and rolling it into granules, usually 2–4 mm in diameter, in rotating drums. The granular type has a high drill-ability. Double superphosphate contains 45–48 percent available P2O5 and very little gypsum, and is usually made in granular form. Ammoniated superphosphate contains, in addition to 14–19.5 percent available P2O5, not less than 1.6 percent ammonia. Manganese superphosphate contains 1.5–2.5 percent manganese, boronated superphosphate contains 0.1–0.3 percent boron, and molybdic superphosphate contains 0.1 percent molybdenum.

Superphosphate is used in all soils as a basic presowing fertilizer; it may be applied at the time of sowing, in which case granular superphosphate is the best type, or for top dressing. It is especially effective in alkaline and neutral soils. In acidic soil the phosphoric acid of the fertilizer is converted into aluminum and iron phosphates, which are difficult for plants to assimilate. In this case, the effectiveness of the superphosphate is increased by mixing it with phosphorite flour, limestone, chalk, and humus before application to limed fields.


Prianishnikov, D. N. Izbr. soch., vol. 1. Moscow, 1965.
Spravochnik po udobreniiam, 3rd ed. Moscow, 1964.
Superfosfat. Moscow, 1969. (Translated from English; edited by A. A. Sokolovskii.)



The most important phosphorus fertilizer, derived by action of sulfuric acid on phosphate rock (mostly tribasic calcium phosphate) to produce a mix of gypsum and monobasic calcium phosphate.


1. a mixture of the diacid calcium salt of orthophosphoric acid Ca(H2PO4)2 with calcium sulphate and small quantities of other phosphates: used as a fertilizer
2. a salt of phosphoric acid formed by incompletely replacing its acidic hydrogen atoms; acid phosphate; hydrogen phosphate
References in periodicals archive ?
In order to determine whether the relevant reactions in superphosphate continue to occur in order to increase the assimilable phosphorus and therefore the conversion rate, by continuing to interact the free acidity present with the insoluble phosphorus of the product.
The fractions of P forms varied among the fertilizers, however, the composts and struvite showed similar ability to provide P to plants in acid soils to the single superphosphate.
The Superphosphate Fertilizerssegment is the most widely used Phosphate fertilizer in theEuropean Phosphatic Fertilizers market.
Ammonia volatilization and ammonium accumulation from urea mixed with zeolite and triple superphosphate.
The current experiment was developed to study the effect of adding acetate (building unit), shikimic acid (precursor of cyclohexane moiety in Rap) and calcium superphosphate (CaP) on biosynthetic rate of Rap.
For example: if the phosphorous (P) and potassium (K) indexes are 1, then grazed grass requires 50 kilograms per hectare (kg/ha) of P, which can be met with triple superphosphate (TSP).
The conductor coatings: pure bone glue; a dried mixture of superphosphate Ca([H.
Fertilizer sources were urea and ammonium sulfate (1:1), either triple superphosphate or mono-ammonium phosphate, and potassium chloride.
Urea and single superphosphate (SSP) were used as source of nitrogen and phosphorus, respectively.
High values were recorded for single superphosphate while the low values were obtained for triple superphosphate P source.
Up to 60 minerals are taken out of the soil during plant production, but only a few are returned in the form of nitrogenous and superphosphate fertilisers; comments Mr John Lawson, General Manager of Development at Global Renewables Australia.