Study On The Production Of Hydroxyapatite From Fish Scales

In this paper, study on preparing higher value-added nano-hydroxyapatite by high temperature firing legal system from fish scale which are extract collagen.It is discuss the way of pretreat on scales powder, calcining temperature and burning time effect on the purity and morphology of nano-hydroxyapatite. And this paper also studied on the dispersion of obtained nano-hydroxyapatite.1. The choice of raw materialsSelect tilapia fish scales, fish scales out of calcium and the scales out of collagen analysis by thermogravimetric analysis (TGA) and differential thermo-analysis (DTA) techniques and Fourier Transform infrared spectroscopy (FTIR) techniques. The results show that the scales out of collagen firing in high temperature can get a purer hydroxyapatite, calcining temperature should be in 800 ~ 1120℃. The concrete calcination conditions should be study in the future.2. The preparation of hydroxyapatiteThe Fourier Transform infrared spectroscopy techniques, X-ray diffraction techniques and scanning electron microscopy are used to analysis the crystal functional group, lattice diffraction and crystal morphology in the single factor experiment to determining the best condition. The results show that without the pretreatment, the rate of temperature for 5 min/℃, keep warm 1h in 900℃, get the best of hydroxyapatite, but still exists the phenomenon of particles reunion serious.Discusses the influence of the purity and morphology of nano-hydroxyapatite when use the method of two time sintering. The experimental results shows that this method could obtain the hydroxyapatite have high purity and uniform size. The size of particle about 100nm, and reunion phenomenon improved. To determine the best sintered conditions for: the rate of temperature for 5 min/℃, keep warm 30min in 641℃, with furnace cooling, and then the rate of temperature for 5 min/℃, keep warm 1h in 900℃.3. The dispersion of hydroxyapatiteThe dispersion of obtain hydroxyapatite be studied. Experiments showed that the preparation of hydroxyapatite particles have not good dispersion in water. When add the dispersant, the dispersion of particle hydroxyapatite has improved significantly.To spread rate as an index, research the relevant of dispersion of nanometer hydroxyapatite with dispersant concentration, ultrasonic time and the ultrasonic frequency. The single factor experiment results show that when the gelatin solution concentration for 0.8%, nano hydroxyapatite granules dispersion rate best, aer 61%. Ultrasonic 5min, stop 5min (the whole process as a cycle) ultrasonic cycle for three times, the dispersed rate is best, up to 85%. When the ultrasonic frequency is 45 kHz, the dispersed rate is best, achieved 90%.