EFFECT OF PYROLYSIS TEMPERATURE ON THE TEXTURAL PROPERTIES AND THE ACTIVATION MECHANISM OF PORK BONE DERIVED HYDROXYAPATITE

Authors

  • U. IRIARTE-VELASCO
  • I. SIERRA
  • R. BRAVO
  • J. L. AYASTUY

DOI:

https://doi.org/10.52292/j.laar.2017.291

Keywords:

Hydroxyapatite, Bone char, Chemical activation, Physicochemical characterization, TG-MS

Abstract

Calcium hydroxyapatite was produced from pork bones through a three step procedure including pre-pyrolysis, chemical impregnation with K2CO3 and pyrolysis. The effect of pyrolysis temperature on the porosity development of the material was investigated. The specific surface area (SSA) decreases as charring temperature increases. It is observed that the chemical treatment with K2CO3 is inefficient at mild pyrolysis conditions, in the 550-700ºC range. On the contrary, micropore, mesopore and macropore formation is enhanced by chemical activation with K2CO3 at about 800ºC. The reactions involved during the chemical activation step were analysed by mass spectrometry. It was concluded that treatment with K2CO3 favours the release of water and CO. this phenomenon was related to SSA and pore volume development. On the contrary, activation at 900 ºC caused a remarkable reduction in SSA, especially for K2CO3 treated samples, due to excessive ongoing of the above reactions as deduced from the pyrolysis gases.

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Published

2019-10-17