Morphology controlled calcium ortho phosphates induced by chemical additions under hydrothermal reaction


  • Dujreutai Pongkao Kashima Faculty of Science, Chulalongkorn University
  • Ekarat Kongkul Faculty of Science, Chulalongkorn University
  • Torpong Daopradubwong Faculty of Science, Chulalongkorn University


Calcium Phosphate, Hydroxyapatite, Whisker, Hydrothermal


Morphology controlled calcium orthophosphates under hydrothermal reaction was achieved using saturated solution of monocalcium phosphate monohydrate (MCPM) as a starting material. MCPM saturated solution was hydrothermally treated at 180°C for 4 and 12 hrs. Citric acid as a chelating agent and a mixed solution of NaNO3and NaF were individually added into the reactor. The morphologies, phases and microstructures of the obtained products were characterized by optical microscope (OM), X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. Irregular shape crystals were obtained when a saturated solution of MCPM was autoclaved at 180°C for 4 hrs. Though citric acid was added into the reaction, the irregular shape products were still obtained with a minority of hexagonal plate crystals. As a result, the whiskers were synthesized when the mixed solution of NaNO3+ NaF was added into MCPM saturated solution and treated at 180°C for 12 hrs. Although the reaction time decreased from 12 to 4 hrs, the whisker products were still obtained. Phase analyses clarified by XRD that the whiskers were hydroxyapatite.


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How to Cite

D. P. Kashima, E. Kongkul, and T. Daopradubwong, “Morphology controlled calcium ortho phosphates induced by chemical additions under hydrothermal reaction”, J Met Mater Miner, vol. 18, no. 1, Apr. 2017.



Original Research Articles