Phase equilibrium measurements of acoustically levitated squalane–CO₂ mixtures by Raman spectroscopy

Abstract

This work describes the phase equilibrium measurements of acoustically levitated binary mixtures with concentration measurements using Raman spectroscopy without sample extraction of the autoclave. The levitator design is implemented in a Single‐Droplet Optical Cell for levitation processes under varying atmospheres. The advantages of acoustic levitation of small droplets under increased temperatures and pressure combined with spectroscopic applications like Raman spectroscopy enable novel experiments possibly relevant to the fields of chemical engineering. To the author's knowledge, this is the first use of Raman spectroscopy for phase equilibria investigations on acoustically levitated droplets under high pressure and temperature. The results show very good agreements with literature data. Copyright © 2014 John Wiley & Sons, Ltd.

Recent advances in linear and non‐linear Raman spectroscopy. Part IX

“…To the authors' knowledge, this is the first use of Raman spectroscopy for phase equilibrium investigations on acoustically levitated droplets under high pressure and temperature. The results show very good agreements with literature data …”

Photochemistry of single particles using acoustic levitation coupled with Raman microspectrometry

“…So far, levitation‐based setups, i.e. optical levitation, electrodynamic balance and ultrasonic trapping, have been shown to be suitable and powerful techniques for wall‐less investigations. When coupled with micro‐Raman scattering, the composition, size and phase partitioning of different chemical components within a liquid or solid droplet can be investigated, and then, many fundamental physical and chemical processes at the single particle scale with in situ conditions have been unravelled .…”

Measurement of Secondary Structure Changes in Poly-L-lysine and Lysozyme during Acoustically Levitated Single Droplet Drying Experiments by In Situ Raman Spectroscopy

“…Furthermore, Raman spectroscopy measurements on levitated samples are another broad field of application. Examples are the investigation of the evaporation behavior and the phase equilibrium of binary mixtures [23,24], the tracking of the dynamics of red blood cells, the detection of hemozoin in malaria-infected cells [25], the identification and environmental monitoring of algal cells [26], and the composition profiling of drying multi-component droplets [27]. In addition to the described applicability to acoustic levitators, Raman spectroscopy is a suitable tool for the qualitative and quantitative analysis of structural elements (in particular the secondary structural elements) of proteins [28].…”