Thermodynamic measurements of CO2 containing systems

1
Thermodynamic measurements of CO2 containing
systems

• NASA SHARP Plus
• Alessandra Carreon

2
Overview

• Importance of measurements
• Experimental design
• Operational procedures
• GC Features
• GC Online sampling system
• GC Calibration procedure
• GC Calibration results

3
Importance of VLE measurements

• The binary phase behavior of systems containing
  carbon dioxide is of interest to the industry and
  the academia.
• The data measured using the VLE apparatus is
  utilized by industries in designing separation
  processes and supercritical fluid extraction.

4
Experimental Design
5
Operational procedures

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• This is a continuous flow apparatus where the
  feed enters the equilibrium cell and the
  separated vapor and liquid phases are
  continuously recirculated back into the feed tank
  by means of a recirculation pump.
• Constant temperature and pressure conditions are
  maintained in the equilibrium cell by means of a
  control valve and Environmental chambers.
• The liquid level in the cell can be monitored by
  a Jerguson gage.

6
Operational Procedures (cont.)

• The criterion for equilibrium are attainment of
  constant pressure and constant liquid level.
• After attaining equilibrium, samples are analyzed
  by the GC.

7
GC Features

• Electronic Pressure Control (EPC)
• Insulated column oven
• Thermal Conductivity Detector (TCD)
• Flame Ionization Detector
• PeakSimple Software

8
GC Online sampling system

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9
GC Calibration procedure

• Carrier gas flow is maintained throughout the GC
• Gas samples are injected into the GC at differing
  pressures, resulting in varied densities. These
  densities in turn account for the diverse area
  values obtained.
• The temperature within the valve oven is
  maintained at 30C.

10
GC Calibration results

• Chromatograms viewed with PeakSimple Software
• CO2 Calibration curve
• CH2F2 Calibration curve

11
DFM Calibration curve
12
CO2 calibration curve