Model apatite systems for the stabilization of toxic metals : I, calcium lead vanadate
Apatites of composition (Ca10−xPbx)(VO4)6F2 with 0 ≤x≤ 9 were synthesized by sintering in air at 800°C the oxides of calcium, lead, and vanadium that were mixed with calcium fluoride. Variations in lattice parameters, grain size, and durability were monitored as a function of composition. The expect...
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| Format: | Journal Article |
| Language: | English |
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2013
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| Online Access: | https://hdl.handle.net/10356/95671 http://hdl.handle.net/10220/9477 |
| _version_ | 1824456917274066944 |
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| author | Dong, Zhili White, Timothy John Wei, Bing Laursen, Karin |
| author2 | School of Materials Science & Engineering |
| author_facet | School of Materials Science & Engineering Dong, Zhili White, Timothy John Wei, Bing Laursen, Karin |
| author_sort | Dong, Zhili |
| collection | NTU |
| description | Apatites of composition (Ca10−xPbx)(VO4)6F2 with 0 ≤x≤ 9 were synthesized by sintering in air at 800°C the oxides of calcium, lead, and vanadium that were mixed with calcium fluoride. Variations in lattice parameters, grain size, and durability were monitored as a function of composition. The expected dilation in unit cell edges with increasing replacement of calcium (IR = 1.26 Å) by lead (IR = 1.45 Å) was observed. The a cell edge (in angstroms) varied linearly (0.0458 x+ 9.7068) with x, while c followed the binomial function 0.0018x2+ 0.0279x+ 7.0118. Average grain sizes increased from approximately 5 μm (x= 0) to 25 μm (x= 9) as grain growth was enhanced due to incipient melting of the lead-rich compositions. For x < 5 the materials were biphasic. Overall dissolution, as determined by the toxicity characteristic leaching procedure (TCLP), was faster in calcium-rich apatites. Etching of well-crystallized apatite grains occurred preferentially on {1010} faces. These leach losses were augmented through the more rapid removal of cryptocrystalline regions and intergranular thin films. |
| first_indexed | 2025-02-19T04:01:43Z |
| format | Journal Article |
| id | ntu-10356/95671 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2025-02-19T04:01:43Z |
| publishDate | 2013 |
| record_format | dspace |
| spelling | ntu-10356/956712023-07-14T15:53:59Z Model apatite systems for the stabilization of toxic metals : I, calcium lead vanadate Dong, Zhili White, Timothy John Wei, Bing Laursen, Karin School of Materials Science & Engineering DRNTU::Engineering::Materials Apatites of composition (Ca10−xPbx)(VO4)6F2 with 0 ≤x≤ 9 were synthesized by sintering in air at 800°C the oxides of calcium, lead, and vanadium that were mixed with calcium fluoride. Variations in lattice parameters, grain size, and durability were monitored as a function of composition. The expected dilation in unit cell edges with increasing replacement of calcium (IR = 1.26 Å) by lead (IR = 1.45 Å) was observed. The a cell edge (in angstroms) varied linearly (0.0458 x+ 9.7068) with x, while c followed the binomial function 0.0018x2+ 0.0279x+ 7.0118. Average grain sizes increased from approximately 5 μm (x= 0) to 25 μm (x= 9) as grain growth was enhanced due to incipient melting of the lead-rich compositions. For x < 5 the materials were biphasic. Overall dissolution, as determined by the toxicity characteristic leaching procedure (TCLP), was faster in calcium-rich apatites. Etching of well-crystallized apatite grains occurred preferentially on {1010} faces. These leach losses were augmented through the more rapid removal of cryptocrystalline regions and intergranular thin films. Accepted version 2013-04-10T08:18:01Z 2019-12-06T19:19:31Z 2013-04-10T08:18:01Z 2019-12-06T19:19:31Z 2002 2002 Journal Article Dong, Z., White, T. J., Wei, B., & Laursen, K. (2002). Model Apatite Systems for the Stabilization of Toxic Metals: I, Calcium Lead Vanadate. Journal of the American Ceramic Society, 85(10), 2515-2522. 0002-7820 https://hdl.handle.net/10356/95671 http://hdl.handle.net/10220/9477 10.1111/j.1151-2916.2002.tb00489.x en Journal of the American ceramic society © 2002 The American Ceramic Society. This is the author created version of a work that has been peer reviewed and accepted for publication by Journal of the American Ceramic Society, The American Ceramic Society. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1111/j.1151-2916.2002.tb00489.x ]. application/pdf |
| spellingShingle | DRNTU::Engineering::Materials Dong, Zhili White, Timothy John Wei, Bing Laursen, Karin Model apatite systems for the stabilization of toxic metals : I, calcium lead vanadate |
| title | Model apatite systems for the stabilization of toxic metals : I, calcium lead vanadate |
| title_full | Model apatite systems for the stabilization of toxic metals : I, calcium lead vanadate |
| title_fullStr | Model apatite systems for the stabilization of toxic metals : I, calcium lead vanadate |
| title_full_unstemmed | Model apatite systems for the stabilization of toxic metals : I, calcium lead vanadate |
| title_short | Model apatite systems for the stabilization of toxic metals : I, calcium lead vanadate |
| title_sort | model apatite systems for the stabilization of toxic metals i calcium lead vanadate |
| topic | DRNTU::Engineering::Materials |
| url | https://hdl.handle.net/10356/95671 http://hdl.handle.net/10220/9477 |
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