Abstract

Abstract The cation-exchange characteristics between Pb2+ ions of aqueous solutions containing counter-anions (F−, C1−) and Ca2+ ions of synthetic hydroxyapatite samples have been investigated in detail under the conditions of low pH values (3.0, 4.0 and 5.0) by a normal batch method. Even at the low pH value of 3.0 the apatite structure in a solution containing F− or C1− ions was maintained via a concurrent ion-exchange effect of Pb2+ ions together with F− or C1−ions, which are known to be exchangeable with OH- ions of the apatite. Moreover, it was found that Ca2+ ions in the apatite sample can easily be exchanged for Pb2+ ions almost without distinction between MI and M2 sites, assisted by the loosening effect of protons even at room temperature. Next, it was found that the hydroxyapatite samples are transformed into amorphous states by the reactions between Ca 2+ ions in the samples and Sn 2+ ions in the SnC12 acidic aqueous solutions with pH of 3.0 or below with a molar ratio of Sn2+/Ca2+ -1.0. The ex...

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.