Zur Einwirkung von Fluorid verschiedener Konzentration auf Hydroxylapatit

Application of the solubility-product principle to the dissolution of phosphate rock

“…This is larger than the value of 9.84 given by Lindsay and Moreno (i960). Rathje (1957b) gives The measurements made with hydroxyapatite provide also some information of the same kind as that obtained in the first experimental work, together with additional evidence.…”

“…He did not succeed in precipitating pure fluorapatite because at lower pH values no precipitation took place, as he pointed out. Rathje (1957b) investigated also the effect of fluoride ions on precipitated hydroxyapatite. He showed that in the presence of a fluoride ion concentration higher than that corresponding to the saturated solution of calcium fluoride, decomposition of the hydroxyapatite occurred, with the con current formation of calcium fluoride.…”

Behavior of phosphate rock in soils and its availability to plants

“…for the mineral francolite. Rathje (1957) suggested that some phosphate rock is composed of a mixture of two minerals, hydroxylfluorapatite and fluorite. The composition of phosphate rock is now known to vary from one deposit to another.…”

Application of the solubility-product principle to the dissolution of phosphate rock

“…This is larger than the value of 9.84 given by Lindsay and Moreno (i960). Rathje (1957b) gives a solubility of calcium fluoride equal to 15 mg. per The measurements made with hydroxyapatite provide also some information of the same kind as that obtained in the first experimental work, together with additional evidence.…”

“…He did not succeed in precipitating pure fluorapatite because at lower pH values no precipitation took place, as he pointed out. Rathje (1957b) The solubility product of hydroxyapatite was expressed by the relation 4pCa + 3PHPC>4 -2pH = 7.5 (or 6.5) ,…”