Phosphate diammonium

Minerals. Supplementation of macrominerals to mminants is sometimes necessary. Calcium and phosphoms are the minerals most often supplemented in mminant diets. One or both may be deficient, and the level of one affects the utilization of the other. Limestone, 36% calcium, is commonly used as a source of supplemental calcium. Dolomite, 22% calcium oyster sheUs, 35% calcium and gypsum, 29% calcium, are sources of calcium. Bone meal, 29% calcium, 14% phosphoms dicalcium phosphate, 25—28% calcium, 18—21% phosphoms and defluorinated rock phosphate, 32% calcium, 18% phosphoms, are sources of both calcium and phosphoms. Diammonium phosphate, 25% phosphoms phosphoric acid, 32% phosphoms sodium phosphate, 22% phosphoms and sodium tripolyphosphate, 31% phosphoms, are additional sources of phosphoms (5). 

Fig. 2. Fertilizers in the prilled or granular form (a), prilled ammonium nitrate (b), prilled urea (c), granular urea (d), granular diammonium phosphate ...

The routes by which mineral phosphates are processed into finished fertilizers are outlined in Eigure 7. World and U.S. trends in the types of products produced are shown in Eigures 8 and 9, respectively. Most notable in both instances is the large, steady increase in the importance of monoammonium and diammonium phosphates as finished phosphate fertilizers at the expense of ordinary superphosphate, and to some extent at the expense of triple superphosphate. In the United States, about 65% of the total phosphate appHed is now in the form of granular ammonium phosphates, and additional amounts of ammonium phosphates are appHed as integral parts of granulated mixtures and fluid fertilizers. 

Since about 1968, triple superphosphate has been far outdistanced by diammonium phosphate as the principal phosphate fertilizer, both in the United States and worldwide. However, production of triple superphosphate is expected to persist at a moderate level for two reasons (/) at the location of a phosphoric acid—diammonium phosphate complex, production of triple superphosphate is a convenient way of using sludge acid that is too impure for diammonium phosphate production and (2) the absence of nitrogen in triple superphosphate makes it the preferred source of phosphoms for the no-nitrogen bulk-blend fertilizers that frequendy are prescribed for leguminous crops such as soy beans, alfalfa, and clover. 

A flow sheet of the basic TVA process for granular diammonium phosphate is given in Figure 12. The raw materials are wet-process phosphoric acid and anhydrous ammonia. Feed acid concentration of at least 40% P2 5 required to give a satisfactory water balance. This average concentration usually is provided by two separate feed streams, one of 54% P2 5 concentration and one of about 30% P2 5 arrangement shown, the 54% acid is... 

Fig. 13. Pieneutializei vessel of the type used in production of granular diammonium phosphate and mixed fertilizets.

Table 8. Specifications of Fertilizer-Grade Granular Diammonium Phosphate ...

Monoammonium Phosphate. Monoammonium phosphate [7722-76-1] (MAP), NH4H2PO4, has become second only to diammonium phosphate as a phosphate fertilizer material of trade. During the year ended June 30, 1990, monoammonium phosphate used ia the United States furnished 985 thousand t of P2O5 as compared to 1.5 million t furnished by diammonium phosphate and 240 thousand t by triple superphosphate (Fig. 7). Monoammonium phosphate furnished 25% of total P2O5 consumption. 

Formulatio n Borax Boric acid Diammonium phosphate Sodium phosphate dodecahydrate Other... 

Ammonium chloride [12125-02-9], ammonium sulfate [7783-20-2], and diammonium phosphate [7708-28-0] have also been used for shale stabilization (102,103). Ammonium ions have essentially the same effect on shales as potassium ions but use of ammonium salts is often objectionable because of the alkaline nature of the mud. In the North Sea and northern Europe, where magnesium-bearing salt formations ate encountered, magnesium chloride [7786-30-3] is used, but in the United States it is used only on a small scale. 

Monoammonium and diammonium phosphates are produced on a large scale as fertilizers. During the 1970s, these materials, produced from economical wet-process phosphoric acid, became the world s leading phosphate fertilizers. 

Evolution of ammonia from a boiling dilute solution of diammonium phosphate gradually reduces the pH. This process is used commercially to control the precipitation of alkaH-soluble—acid-insoluble coUoidal dyes on wool. Other ammonium orthophosphate salts of interest are ammonium hemiphosphate [28537-48-6] NH4H2PO4 H3PO4, and its hydrate [28037-74-3], as well as the trihydrate [78436-07-4] of DAP. 

In an alternative industrial process, resorcinol [108-46-3] is autoclaved with ammonia for 2—6 h at 200—230°C under a pressurized nitrogen atmosphere, 2.2—3.5 MPa (22—35 atm). Diammonium phosphate, ammonium molybdate, ammonium sulfite, or arsenic pentoxide maybe used as a catalyst to give yields of 60—94% with 85—90% selectivity for 3-aminophenol (67,68). A vapor-phase system operating at 320°C using a siUcon dioxide catalyst impregnated with gallium sesquioxide gives a 26—31% conversion of resorcinol with a 96—99% selectivity for 3-aminophenol (69). 

Markets. Industrial use of ammonia varies according to region. Eor example, industrial usage represents 20% of the ammonia production in the United States and Western Europe, 10% in the USSR, 1—10% in Asia, and 5% in Latin America and North Africa (79). Fertiliser ammonia consumed domestically in most countries is converted to straight or compound fertilisers such as urea, ammonium nitrate, diammonium phosphate, and various grades of mixed fertilisers. However, almost 29% of ammonia nitrogen in the United States is consumed as direct appHcation material. The use of nitrogen solution such as urea and ammonium nitrate (UAN) has also become popular in the United States and the USSR. 

Chisso-Asahi Fertilizer Company, Ltd. This company utilizes thermoplastic resins, such as polyolefins, poly(vinyhdene chloride), and copolymers, as their coating materials. The coatings are dissolved in fast-drying chlorinated hydrocarbon solvents and are appHed to a variety of substrates including urea, diammonium phosphate [7783-28-0] potassium sulfate [7778-80-3], potassium chloride [7447-40-7], and ammonium nitrate/potassium sulfate-based N—P—K fertilizers. 

Phosphate Fertilizer Industry Diammonium Phosphate Plants... 

Superphosphoric acid, diammonium phosphate, triple superphosphate and granular triple superphosphate. 

Diammonium phosphate Gaseous F, NH, Venturi or cyclonic scrubber with 30% phosphoric acid... 

Monoammonium phosphate Diammonium phosphate Nitric oxide Actylonitrile Caprolactam Monomethylamine Dimetliylamine Hexametliylenetetramine Trimetliylamine Monoethanolamine Dietlianolamine Trietlianolamine Hydrogen Cyanide Fatty nitrogen compounds (nitriles, amines, quaternary ammonimn compounds)... 

Sugama, T. Kukacka, L. E. (1983a). Magnesium monophosphate cements derived from diammonium phosphate solutions. Cement Concrete Research, 13, 407-16. 

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