Enthalpy of silicate melts from 1520 to 2600 K under ambient pressure. [Liquid SiO/sub 2/, CaSiO/sub 3/, and CaMgSi/sub 2/O/sub 6/]

Journal Article · Wed Dec 01 00:00:00 EST 1982 · High Temp. Sci.; (United States)

OSTI ID:5685550

Stout, N D; Piwinskii, A J

We measured the enthalpy increments, H/sub T/-H/sub 298/, for liquid SiO/sub 2/, CaSiO/sub 3/, and CaMgSi/sub 2/O/sub 6/ over the temperature range 1700-2600 K. Experimental enthalpies for CaSiO/sub 3/ and CaMgSi/sub 2/O/sub 6/ are higher than estimates based on simple additivity by 15-20% at 2000 K. Heat capacities were independent of temperature. We calculated partial molal heat capacities for CaO and MgO liquids from the enthalpy data. We also measured the enthalpies of five polycomponent melts obtained by fusing various rocks collected from the Department of Energy Nevada Test Site; these were measured over the range 1520-2600 K. Two of these compositions showed a temperature trend in their heat capacities, indicating that models that assume temperature-independent partial molal heat capacities may be inadequate for estimating thermal properties of complex liquid silicates.

• Research Organization: Lawrence Livermore National Lab., CA
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5685550
• Journal Information: High Temp. Sci.; (United States), Vol. 15:4
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CALCIUM SILICATES
ENTHALPY
SPECIFIC HEAT
MAGNESIUM SILICATES
SILICON OXIDES
MOLECULAR WEIGHT
NEVADA TEST SITE
VERY HIGH TEMPERATURE
ALKALINE EARTH METAL COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
MAGNESIUM COMPOUNDS
NATIONAL ORGANIZATIONS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SILICATES
SILICON COMPOUNDS
THERMODYNAMIC PROPERTIES
US DOE
US ORGANIZATIONS
360603* - Materials- Properties