High Pressure Separations of Supercritical Nitrogen and Carbon Dioxide
Supercritical fluids exist at high pressures and offer potential for effective and efficient separations. This investigation involves exploring the equilibrium behavior of supercritical fluid mixtures with two or more species, one being carbon dioxide (CO₂). Teledyne Isco 260D syringe pumps are essential parts of the experimental apparatus used in the investigation, which is located in the Carbon Recycling Center in the Depart- ment of Biological Engineering at the University of Missouri. The pumps precisely meter pure fluids into the high pressure separation chamber. The results describe a nonhomogeneous supercritical fluid mixture with density driven concentration gradients at pres- sures greater than 20 MPa and temperatures at ambient or below. Most supercritical fluids and supercritical fluid mixtures are thought to be homogeneous; however, for a binary or tertiary mixture, the term supercritical is more arbitrary than for a pure substance. This kind of separation has “carbon capture” applications in contin- uous processing of pressurized gasification products, other biomass refinery operations, and in the natural gas industry.
Doug Hendry¹, Nikolas Wilkinson², Reza Espanani², and William Jacoby¹²
Department of Biological Engineering¹, Department of Chemical Engineering², University of Missouri, Columbia, MO
