Trimagnesium phosphate

Crystalline CaHPO 2H20 loses both water molecules in a single step at moderately elevated temperature or upon storage to yield the anhydrous salt. The presence of free moisture accelerates this dehydration, which results in anhydrous dicalcium phosphate, often as a hard mass. Addition of a few percent of tetrasodium pyrophosphate or trimagnesium phosphate, Mg2(P0 2> stabilizes the dihydrate. The mechanism, however, is not well understood. Nonetheless, these materials are used widely to stabilize CaHPO 2H20, particulady for toothpaste appHcations. 

Magnesium Phosphate, Trlbasic. Neutral mag-nesium phosphate tertiary magnesium phosphate trimagnesium phosphate. Mg308P, mol wt 262.86. Mg 27 74%, O 48,70%, P 23.56%. Mg3(PO,h. Oct ahyd rate occurs in nature as the mineral toil ferrite. 

Synonyms cas 7757-86-0 magnesium phosphate, neutral trimagnesium phosphate... 

Trimagnesium bis (orthophosphate) Trimagnesium orthophosphate Trimagnesium phosphate. See Magnesium phosphate tri basic... 

The differences in fertilizer-soil reactions of calcium and magnesium (pyro-) phosphates, respectively, were successfully determined by Raman and synchrotron infrared microspectroscopic studies. All calcium orthophosphates convert to hydroxyapatite in soil over time. On the other hand, magnesium orthophosphates react only as far as trimagnesium phosphate because of then-inability to form an apatite structure. Thus, for the magnesium-based compound, phosphorus remains in a plant-available form. Also, the pyrophosphates of calcium and magnesium react very differently. Calcium pyrophosphate did not react in soil, whereas magnesium pyrophosphate quickly forms dimagnesium phosphate. Furthermore, mineral phases of soils were detectable by infrared microspectroscopy. 

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