Premium
Model Apatite Systems for the Stabilization of Toxic Metals: II, Cation and Metalloid Substitutions in Chlorapatites
Author(s) -
Kim Jean Y.,
Dong Zhili,
White Timothy J.
Publication year - 2005
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2005.00136.x
Subject(s) - leaching (pedology) , apatite , toxicity characteristic leaching procedure , chemistry , crystal structure , ionic bonding , cadmium , inorganic chemistry , materials science , nuclear chemistry , mineralogy , crystallography , ion , metallurgy , environmental chemistry , heavy metals , geology , organic chemistry , soil science , soil water
Environmental chlorapatites, of the form A 10 (B x C 1− x O 4 ) 6 Cl 2 , where A=Ca, Cd, or Pb; B/C=P, V, or Cr and 0≤ x ≤1, were synthesized by solid‐state reactions. Crystal structure variations, primarily lattice parameters, were examined through powder X‐ray diffraction methods, while performance and long‐term durability of these waste form apatites were assessed by a combination of the toxicity characteristic leaching procedure (TCLP) and the American Nuclear Society (ANS) method. As expected, an overall dilation of unit cell edges was observed with increasing ionic substitutions. However, a discontinuity in linearity was often observed, generally for x ≥0.5. The correlation of microstructural changes and leach testing shows that lead chlorapatite is found to be more suitable for waste stabilization than calcium and cadmium analogues.