Phosphates and Apatites

Phosphates usually occur as nonstoichiometic compounds, and their composition often deviates from specific chemical formulas reported in scientific papers. 

PZC/IEP of Adju-Pbos from Superfos Biosector Electrolyte T Method Instrument pH  

1 From AlClj 250 cm of 0.1 M AICI3 was mixed with equal volume of 1 M Nafl2PO4. The mixture was titrated with 500 cm of 1 M NaOH at 5 cmVmin. 

2 From Al(NOj)j 0.5 M AKNO,), was stirred at 40°C for 1 h. Then 0.5 M Na3PO4 was added dropwise until the pH reached 5. The mixture was dialyzed for 10 d, filtered and washed with water for the next 6 d. The precipitate was then dried at 105°C and ground. A portion of the powder was calcined for 1 d at 400 C. 

Properties BET specific surface area 95.2 mVg (uncalcined), 127.5 mVg (calcined) [1097]. 

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M. lijima, H. Tohda, Y. Moriwaki, Growth and structure of lamellar mixed crystals of octacalcium phosphate and apatite in model system of enamel formation, J. Cryst. Growth 116 (1992) 319-326. 

Chaikina M.V. Mechanochemical synthesis of phosphates and apatites - a new way of preparation of complex materials. Phosphorus Research Bulletin 1997 7 35-8. 

Chaikina M.V. The features of chemical interaction in multicomponent system during mechanochemical synthesis of phosphates and apatites. Chem. Sustainable Development 1998 6 13544. 

A variety of potassium, nitrogen, and phosphorous minerals are used to fertilize crops. Gommonly used nitrate compounds are sodium nitrate and potassium nitrate. Ammonium phosphate and apatite are examples of phosphate minerals. 

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