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Determination of vapor-liquid equilibrium data in microfluidic segmented flows at elevated pressures using Raman
Sebastian K Luther1,2, Simon Stehle1,2, Kristian Weihs1
1†Lehrstuhl für Technische Thermodynamik (LTT), Friedrich-Alexander-Universitaet Erlangen-Nuernberg (FAU), Am Weichselgarten 8, 91058 Erlangen, Germany.
Analytical Chemistry
|July 15, 2015
Summary
This study introduces a rapid, noninvasive method using Raman spectroscopy in microcapillary systems to measure vapor-liquid equilibria (VLE). The technique provides accurate VLE data for binary and ternary mixtures at high pressures and temperatures.
Area of Science:
- Chemical Engineering
- Analytical Chemistry
- Spectroscopy
Background:
- Characterizing vapor-liquid equilibria (VLE) is crucial for chemical process design.
- Traditional VLE measurement methods can be time-consuming and invasive.
- Accurate high-pressure VLE data is essential but often limited in existing literature.
Purpose of the Study:
- To develop and present a fast, noninvasive, and efficient analytical strategy for VLE characterization.
- To utilize phase-selective Raman spectroscopy within microcapillary systems (MCS) for VLE measurements.
- To extend the high-pressure VLE database for industrially relevant mixtures.
Main Methods:
- Employed phase-selective Raman spectroscopy within microcapillary systems (MCS).
- Conducted isothermal VLE measurements on binary and ternary mixtures (acetone, water, CO2, N2).
- Operated at elevated pressures up to 10 MPa and temperatures up to 333 K.
Main Results:
- Successfully obtained isothermal VLE data for the specified mixtures.
- Validated the measurement strategy against literature data and reference measurements.
- Generated new VLE data for conditions not previously reported in literature.
Conclusions:
- The presented Raman spectroscopy-based strategy offers a fast and efficient approach for VLE characterization.
- The method is suitable for multiphase flow analysis in microcapillary systems.
- The expanded VLE database contributes valuable data for chemical engineering applications.
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