ビス (オルトリン酸二水素) マグネシウム四水和物の加熱変化
1994 年 1994 巻 251 号 p. 266-271
詳細
1994 年 1994 巻 251 号 p. 266-271
Magnesium bis (hydrogenorthophosphate) tetrahydrate, Mg (H2PO4) 2 4H2O, has been prepared by adding magnesium hydroxide and a small amount of calcium oxide into 60% orthophosphoric acid. Upon heating at a temperature higher than 150°C, the magnesium orthophosphate produced several kinds of chain and ring condensed phosphates. The phosphate composition of the thermal product depended on heating rate. The main thermal dehydrationcondensation reactions were concluded as follows :
(at 150-300°C)
Mg (H2PO4) 2→MgH2P2O7 + H2O
(at a temperature higher than 300°C)
2Mg (H2P2O7) →Mg2P4O12 + 2H2O
All of the magnesium orthophosphate finally converted to magnesium cyclo-tetraphosphate and the overall thermal condensation can be written :
2Mg (H2PO4) 2→Mg2P4O12+4H2O
