Supercritical Carbon Dioxide
Transformation of coexisting gaseous and liquid into supercritical carbon dioxide (scCO2) by heating (for better discrimination of the phase barrier a colored metal complex was added)
Compressed and supercritical carbon dioxide is a well-established solvent for analytical chromatography and large-scale extractions. The extraction of caffeine from green coffee beans was developed by Dr. Kurt Zosel at the Max-Planck-Institut für Kohlenforschung in the late sixties and is nowadays used worldwide for the production of more than 100,000 tons of decaffeinated coffee per year. Most recently, scCO2 has garnered increasing interest as an environmentally friendly alternative solvent for chemical synthesis. Current research efforts at the Max-Planck-Institut für Kohlenforschung are mainly devoted to the utilization of scCO2 as solvent for catalytic processes.