This paper describes a simple constant volume technique that was developed to measure saturated pressure and saturated liquid density of tetramethyl orthosilicate (TMOS). The technique is based on the measurement of temperature and pressure of a liquid undergoing a constant volume heating process. We have observed that during such a process the pressure increases gradually as temperature is increased until the system reaches a take-off point where a rapid pressure rise occurs. Experimenting with methanol and water, we determined that the initial pressure/temperature data (pre take-off) can be used to estimate saturation pressure. We further determined that the take-off point occurs when the liquid expands to fill the container volume, which allows for calculation of the saturated liquid density. Using this information, we estimated and report on the saturated pressure and saturated liquid density of TMOS for temperatures from (60 to 250) deg C.
Compounds
#
Formula
Name
1
C4H12O4Si
silicon tetramethoxide
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.
Type
Compound-#
Property
Variable
Constraint
Phase
Method
#Points
POMD
1
Vapor or sublimation pressure, kPa ; Liquid
Temperature, K; Liquid
Liquid
Gas
Closed cell (Static) method
166
POMD
1
Mass density, kg/m3 ; Liquid
Temperature, K; Liquid
Liquid
Gas
determined from pressure vs temperature measurement to find liquid-full point for a closed cell