The influence of parent-solution chemistry on the precipitation of various Pb-carbonate phases (cerussite, PbCO3(s); hydrocerussite, Pb3(CO3)2(OH)2(s); and phosgenite, Pb2(CO3)Cl2(s)) is studied at 25ºC, 1 bar total pressure in the systems Pb(NO3)2-CO 2-H2O and PbCl2-CO2-H2O. Analysis of both fresh and aged (8 and 16 days), fine-grained Pb-carbonate precipitates resulting from the addition of 0.035 M Pb-bearing (PbCl 2 or Pb(NO3)2) into 0.035 M C-bearing (NaHCO 3 and Na2CO3) reagents (or vice versa ) by powder X-ray diffraction and variable-pressure scanning electron microscopy reveals that: (1) a potential relationship exists between crystal morphology and aqueous speciation (i.e. in the presence of NO3- and Cl-); and (2) solid-phase interconversions between cerussite ↔ hydrocerussite and cerussite ↔ phosgenite readily occurs until equilibrium conditions are achieved in a period of time < 8 days. Further, the precipitation conditions corresponding to various morphologies and habits of cerussite (prismatic, bladed, platy-hexagonal) and phosgenite (tabular, intergrown) is documented.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.98756 |
| Date | January 2005 |
| Creators | Lussier, Aaron J. |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Earth and Planetary Sciences.) |
| Rights | © Aaron J. Lussier, 2005 |
| Relation | alephsysno: 002489100, proquestno: AAIMR24727, Theses scanned by UMI/ProQuest. |
Page generated in 0.0205 seconds