Accession Number : ADP002468

Title :   Pressure-Volume-Temperature Behavior in the System H2O-NaOH-SiO2 and Its Relationship to the Hydrothermal Growth of Quartz,


Personal Author(s) : Kolb,E. D. ; Key,P. L. ; Landise,R. A. ; Simpson,E. E.

Report Date : 1983

Pagination or Media Count : 4

Abstract : We report here a convenient laboratory method for hydrothermal p-V-T measurements and give pressure data in 1.0m NaOH saturated with quartz as a function of temperature up to approx 450 deg. C. Measurements were made at percent fills from 65-89% in isothermal laboratory vessels and in autoclaves with temperature differences like those in quartz growth. These results are compared wtih pressures measured on production sized equipment. The results are used to establish the temperature at which the gas phase disappears under various conditions. Above this temperature delta is constant and rather large. One application of these data is to establish safe operating conditions for the autoclaves used for production growth of quartz. Specifically, the steels used for construction of such autoclaves are brittle below a specific temperature which increases slowly with service. The present p-V-T data can be used to assure that high pressures are avoided at temperatures where the autoclave is brittle.

Descriptors :   *Quartz, *Crystal growth, Transition temperature, Gases, Pressure measurement, Volume, Autoclaves, Brittleness

Distribution Statement : APPROVED FOR PUBLIC RELEASE