Record Details
An investigation of the crystal growth of the heavy metal sulfides in supercritical hydrogen sulfide
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | An investigation of the crystal growth of the heavy metal sulfides in supercritical hydrogen sulfide |
| Names |
Lewis, Leroy Crawford
(creator) Fredericks, William J. (advisor) |
| Date Issued | 1968-01-29 (iso8601) |
| Note | Graduation date: 1968 |
| Abstract | Solubility studies on the heavy metal sulfides in liquid hydrogen sulfide at room temperature were carried out using the isopiestic method. The results were compared with earlier work and with a theoretical result based on Raoult's Law. A relative order for the solubilities of sulfur and the sulfides of tin, lead, mercury, iron, zinc, antimony, arsenic, silver, and cadmium was determined and found to agree with the theoretical result. Hydrogen sulfide is a strong enough oxidizing agent to oxidize stannous sulfide to stannic sulfide in neutral or basic solution (with triethylamine added). In basic solution antimony trisulfide is oxidized to antimony pentasulfide. In basic solution cadmium sulfide apparently forms a bisulfide complex in which three moles of bisulfide ion are bonded to one mole of cadmium sulfide. Measurements were made extending the range over which the volumetric properties of hydrogen sulfide have been investigated to 220°C and 2000 atm. A virial expression in density was used to represent the data. Good agreement, over the entire range investigated, between the virial expressions, earlier work, and the theorem of corresponding states was found. Electrical measurements were made on supercritical hydrogen sulfide over the density range of 10-24 moles per liter and at temperatures from the critical temperature to 220°C. Dielectric constant measurements were represented by a dielectric virial expression. Conductivity measurements were made on pure hydrogen sulfide and on solutions containing, respectively, stannic sulfide, lead sulfide, and triethylammonium chloride. The conductivity of the solutions of stannic sulfide and lead sulfide showed slight increases over the conductivity of the pure solvent. Triethylammonium chloride solutions exhibited a conductivity that was over a thousand times that of the pure hydrogen sulfide at the same density. Virial coefficients derived from both compressibility data and dielectric constant measurements showed evidence of very little (H₂S)x polymer formation. Conductivity measurements indicate a very small solubility for the metal sulfides in hydrogen sulfide, which itself is very slightly ionized. Solutions of triethylammonium chloride are ionized extensively. Crystal growth experiments were undertaken to demonstrate the feasibility of the solution growth of crystals of cadmium sulfide, lead sulfide, silver sulfide, and stannic sulfide from pure supercritical hydrogen sulfide. It was shown that stannic sulfide, lead sulfide, and silver sulfide could be grown from these solutions. Growth rates were extremely slow. |
| Genre | Thesis/Dissertation |
| Topic | Metal crystals |
| Identifier | http://hdl.handle.net/1957/46722 |
