Dr. Zeljko Knez
Sub and Supercritical Processes are main research field of Full Prof. Dr. Knez since 1985. He was Executive Board Member at EFCE and a member of WP of High Pressure Technologies, and was appointed as a president of WP for High Pressure Technology at EFCE from 2003 till 2010. He has published more than 300 paper is SCI journals, his h index is 46 and he has more than 7300 citations. He is author or coauthor of 25 patents and patent applications. He won awards including the Messer Griesheim Innovation Award 1998, National Zois Award from Slovenian Ministry of Science & Technology (1998 and 2006). He is member of European Academy of Sciences and Arts, member of Slovenian Academy of Sciences and Arts and Croatian Academy of Engineering. In 2017 he was between 1 % of top cited researchers on the world.
Sub- and Supercritical Fluids as Solvent for Processes With Low Energy Consumption
High pressure technologies involving sub and supercritical fluids offer the possibility to obtain new products with special characteristics or to design new processes, which are environmentally friendly, sustainable and have low energy consumption. By using high pressure as a processing tool one can also avoid the legal limitations for solvent residues and restrictions on use of conventional solvents in chemical processes. Supercritical fluids are already applied in several processes developed to commercial scale in pharmaceutical, food and textile industries. Extraction of valuable compounds from plant materials and their “in situ” formulation in products with specific properties is one of the very promising applications of high pressure technology with low energy consumption. Particle formation using supercritical fluids may overcome the drawbacks of conventional particle size reduction processes. Because of their unique thermo-dynamic and fluid-dynamic properties, dense gases can also be used for impregnation of solid particles, particle coating, foaming etc. Some biochemical and chemical reactions performed in supercritical fluids have already been implemented at industrial scale to obtain products with high added value. Hydrothermal conversion of biomass is a promising technology for the conversion of waste biomass into biofuels and bio based chemicals. On the other hand, supercritical fluids could be used as heat carriers what is a newly emerging field. A comprehensive investigation into the heat transfer performance of CO 2 , ethane and their azeotropic mixture under supercritical conditions will be presented. To evaluate the potential and the performance of the CO 2 -ethane azeotropic mixture, the coefficients of performance (COP) were calculated for the heat pump working cycle and compared to a system that contains exclusively CO 2 .In our lecture an overview on some applications and future expected development of processes with low energy consumption in the field of sub and supercritical fluids will be presented.
Energy, Subcritical, Supercritical, Fluids, Chemicals, Waste biomass, Processes, Heat transfer, Low energy consumption.