Synthesis Of Porous Hydroxyapatite And Study Of Adsorption Ability Tothe Heavy Metals

Hydroxyapatite?HA?is one of the most widely applied biomaterials.In this thesis,different morphology of porous HA were synthesized by three methods.The influences on the morphology of final porous HA arised by the different experimental conditions and methods were studied d by a series of characterization.1.Golf-like vaterite particles with the average dimension of 1.5 ?m were obtained by a facile mixing-precipitation method in EG-H2 O solution.The vaterite material had a phase transition to calcite as the reaction time prolongs at room temperature.Whereas irregular morphology of vaterite was obtained and phase transition still happened at 80 oC.The golf-like vaterite was used as the precursor with the addition of?NH4?2HPO4,spheric porous HA was prepared by the microwave-hydrothermal method.2.HA powder was prepared by precipitation method as the raw material,porous HA material with uniform porosity was synthesized afterwards which introduced polyvinyl alcohol as pore generator and binder by mixed them and then burned organic constituent away.The influence of sintering ways to the morphology of the products was also discussed.3.HA powder as raw material obtained by precipitation,polystyrene?PS?microspheres as the hole-forming agents and polyvinyl alcohol?PVA?solution as adhesive were used to prepare porous hydroxyapatite?HA?material with uniform size and high porosity through high temperature sintering methond.When the amount of PS was increased to 8 mL,the BET specific surface area reached 7.9643 m2/g.Meanwhile,some adsorption experiments were carried out by using the synthesized porous HA as adsorbent on Pb²⁺,Cu²⁺,Cd²⁺,respectively.The results showed that the adsorption capacity of Pb²⁺,Cd²⁺ and Cu²⁺ by the porous materials was 99.9%,34.5% and 28.5% after 4 h,respectively.