Synthesis of phosphate-silicate apatites at atmospheric pressure

✍ Scribed by L. Boyer; J. Carpena; J.L. Lacout

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 546 KB
• Volume: 95
• Category: Article
• ISSN: 0167-2738
• DOI: 10.1016/s0167-2738(96)00571-1

✦ Synopsis

Natural

silicate-containing apatites (called britholites) are found in rare geological areas and contain large amounts of actinide and lanthanide elements [l-3]. Such compounds can be synthetised by a solid state reaction at high temperatures. As for the well-known fluoroapatite Ca,,(PO,),F, and oxyapatite Ca,,(PO,),OU (0 = vacancy) these compounds were prepared by the substitution pair (La", Sioux ) for (Ca", PO:-). The general formula of the compounds are given by Ca ,I,~,La~(SiO,),(PO,),_,F,, ()%x56, and Ca,,,_r La~(SiO,)x(PO,),_~OO, 05x%6. They were analysed by X-ray diffraction and infrared spectroscopy. The synthesis has to be performed accurately to avoid the formation of poorly reactive intermediate phases.