Phosphoric acid and phosphates

S. cerevisiae is produced by fed-batch processes in which molasses supplemented with sources of nitrogen and phosphoms, such as ammonia, ammonium sulfate, ammonium phosphate, and phosphoric acid, are fed incrementally to meet nutritional requirements of the yeast during growth. Large (150 to 300 m ) total volume aerated fermentors provided with internal coils for cooling water are employed in these processes (5). Substrates and nutrients ate sterilized in a heat exchanger and then fed to a cleaned—sanitized fermentor to minimize contamination problems. 

Uses. The principal use of monosodium phosphate is as a water-soluble soHd acid and pH buffer, primarily in acid-type cleaners. The double salt, NaH2P04 H PO, referred to as hemisodium orthophosphate or sodium hemiphosphate, is often generated in situ from monosodium phosphate and phosphoric acid in these types of formulations. Mixtures of mono- and disodium phosphates are used in textile processing, food manufacture, and other industries to control pH at 4—9. Monosodium phosphate is also used in boiler-water treatment, as a precipitant for polyvalent metal ions, and as an animal-feed supplement. 

Both monocalcium phosphate and dicalcium phosphate dissolve incongmently in water, disproportionating to more basic calcium phosphate and phosphoric acid. The extent of these reactions varies with the temperature and the amount of water. If water is added gradually to anhydrous monocalcium phosphate, equiUbrium conditions first correspond to a mixture of the anhydrous salt and its monohydrate. After conversion to the monohydrate, further reaction affords dicalcium phosphate plus free phosphoric acid. Dicalcium phosphate decomposes in aqueous solution to the more basic hydroxyapatite and phosphoric acid via intermediate octacalcium phosphate. The compHcated stepwise conversion of the acidic mono- and dicalcium phosphates to hydroxyapatite is summarized in equations 6—9. The kinetics are quite complex. 

P. Becker, Phosphates and Phosphoric Acid, Marcel Dekker, New York, 1988, 760 pp. 

Guidelines for the framework indicate that the phosphorus atom is in the middle, bonded to the four oxygen atoms. By recognizing the link between dihydrogen phosphate and phosphoric acid, we know that the hydrogen atoms bond to two of the oxygen atoms. 

Operating staff at the plant consist of two operators per shift plus one maintenance person on dayshift. The wastewater is nutrient deficient and a ratio of 100 8 1 of BOD N P is maintained by the addition of diammonium phosphate and phosphoric acid for nitrogen and phosphorous requirements, respectively. 

More successful applications of periodate oxidation to substituted sugars were made employing the sugar phosphates and phosphoric acids,63 66 the chloraloses, 62 70 the benzyl ethers of sugars,71 72 a dimethyleneoxy sugar,73... 

Becker, P., Phosphates and Phosphoric Acid, 2nd. ed., Marcel Dekker, New York, 1989. McCoubry, J. C., in Industrial Inorganic Chemicals Production and Use, Thompson, R., Ed., Royal Society of Chemistry, Cambridge, 1995, 379. 

Photolytlc. Malathion absorbs UV light at wavelengths more than 290 nm indicating direct photolysis should occur (Gore et al, 1971). When malathion was exposed to UV light, malathion monoacid, malathion diacid, 0,0-diethyl phosphorothioic acid, dimethyl phosphate, and phosphoric acid were formed (Mosher and Kadoum, 1972). 

Soil. Cleavage of the molecule yields diethyl phosphate, monoethyl phosphate, and phosphoric acid (Hartley and Kidd, 1987). 

Becker, P. Phosphates and Phosphoric acid. Fertilizer Science and Technology Series, Vol. 6,... 

It would be interesting to test the reversal of the 7r-A isotherms with monolayers of long-chain phosphates, but the only data available to our knowledge are for octadecyl phosphates and phosphoric acids over... 

In addition to the polymer substrate, a series of binding resins made from polyamide and polyimide, polyphenylsulfide (PPS), polyether sulfone (PES) and/or silicone resin are necessary for applying the coating. Such substances like laminating agents (lithium polysilicate, aluminum phosphate and phosphoric acid) and various additives are also used. Included in these additives are emulsifiers and further processing aids (e.g. silicone oil). 

Figure 16.13 Structures of Ru(bpy)3-based fluorescent phosphate and phosphoric acid ester sensors...

The resulting product is a mixture of dialkyl and monoalkyl phosphate esters. These products also contain small amounts of condensed phosphates and phosphoric acid. Neutralization of the acids with bases like alkali hydroxides, ammonia, or amines produces water-soluble anionic surfactants and emulsifiers. 

Marzulli, F.N. Callahan, J.F. Brown, D.W. Chemical structure and skin penetrating capacity of a short series of organic phosphates and phosphoric acid. J. Invest. Dermatol. 1965, 44, 339-344. 

Becker, P., "Phosphate and Phosphoric Acid," Marcel Dekker, Inc., New York and Basel, 1983. 

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