The objective of the present study was the qualitative comparison of hydroxyapatite (HAP) extracted from bio waste by different methods. Fish bones obtained from mango fish (Oreochromis niloticus) were used as natural source for HAP synthesis. Three different processes were applied to extract the natural HAP: annealing at 400-1000 °C (F400-F1000), H2O2cleaning and NaOH cleaning. A combination of TGA/DSC analyses, XRD spectrometry, FTIR spectroscopy and scanning electron microscopy were utilized for characterization. They indicated that all methods have the ability to eliminate the organic compounds present in the fish bones. However, annealing of the bone sample was found to be more efficient approach in reducing the amount of organic phase; only inorganic phase was remained in F600, F800 and F1000. For the HAP crystallinity, treatment with H2O2, NaOH, and heating up to 400 °C did not create notable changes of HAP original crystallinity. On the contrary, HAP crystallinity was increased slowly from 400 to 600 °C, outstandingly from 600 to 800 °C and remained almost constant from 800 to 1000 °C.
Synthesis and characterization of pure natural hydroxyapatite from fishbone biowaste of coastal communities