Thermodynamic properties of carbon dioxide expanded liquids and applications in chemical reactions

Carbon dioxide expanded liquids (CXLs) have been considered as a kind of environmentally benign solvents. They often present some unique features such as high gas solubility, good mass transfer property, low viscosity, mild operation conditions, as well as less employment of organic solvents. So they are given more and more attentions by chemists and chemical engineering scientists. This paper reviews the recent studies on the volume expansibility, phase equilibrium thermodynamics, mass transfer properties, acidities, and conductivities of CXLs, and summarizes the chemical reactions based on the CXLs, including hydrogenation, hydroformylation and oxidation etc. Finally, the existing problems associated with the CXLs are analyzed and the research directions of CXLs in future are also pointed out.