1. Solvent Cycle, Methods for Solute Precipitation Heat and Mass Transfer: High Pressure chemical Engineering I (WS) Chapter 7

2. Flow Scheme of a Solvent Cycle

3. Solvent Cycle Steps: separate the extract from the solvent (1), clean the solvent for reuse (2), remove the solvent from raffinate (3), adjust composition of solvent mixture (if applicable) (4). Solvent Cycle

4. Single stage Multiple stage Counter- Chromato- (precipitation) current graphic SFE Modes of Operation

5. Extraction From Solids S t S / F Essential oils(5 %) 20 20 Edible oils(2 %) 40 < 1  40 Coffee decaffeination (0.01 %) 200  5  40 Black tea decaff. (0.01 %) 230  1.5  150 Total amount of solvent S, kg/kg F Extraction time t, h Solvent to Feed Ratio S/F, kg S /(kg F h) Basis: Solvent: Carbon dioxide 10 - 30 MPa, 330 K Solvent Cycle: Solvent to feed ratio of SFE processes

6. Countercurrent Separation V/L v S / F FAEE, FAME (5 %)  20 7.5  125 FFA (fatty acids) (2 %) 50 4.5  50 Squalene (1.5 %)  20 10  50 Tocopherol-Purif. (2.5 %) 35  20  45 Solvent ratio V/L, kg/kg Reflux ratio v, - Solvent to feed ratio S/F, kg F /kg F Basis: Solvent: Carbon dioxide 10 - 30 MPa, 350 K Solvent Cycle: Solvent to feed ratio of SFE processes

7. Chromatographic Separation P r t r S / F DHA / DPA  1.5 15 900 x 10 3 EM Phytol-isomers 10- 30 6  900 EM  200 SMB Productivity Pr, g P /(kg StPh h) Retention time, min Solvent to feed ratio S/F, kg F /kg F Basis: Solvent: Carbon dioxide 10 - 30 MPa, 310 K Solvent Cycle: Solvent to feed ratio of SFE processes

8. Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment...... Modes For Product Recovery

9. Birtigh, Brunner, Johannsen Solubility of Caffeine in CO 2

10. Gas Circuit in the Compressor Mode

11. Compressor Process, Throttling Sub-Critical

12. Compressor Process, Throttling Super- Critical

13. Pump Process

14. Pump Process, Throttling, Sub-Critical

15. Pump Process, Throttling Super- Critical

16. Extraction temperature: 313 K Energy Consumption by Various Solvent Cycles

17. Mechanical Energy Thermal energy in Thermal energy out Pump with heat recovery Pump without heat recovery Compressor with heat recovery Compressor without heat recovery Extraction pressure [MPa] Energy [kJ/kg] Energy needed for the gas cycle  70 kJ/kg CO2  95 kJ/kg CO2 for S/F 125 kg/kg: 8750 kJ/kg Feed 11875 kJ/kg Feed

18. Reduction of pressure or density (temperature) Anti solvent Membrane separation Adsorption Absorption De-Entrainment Modes For Product Recovery

19. Brunner 1983 Solubility in a Gas With a Modifier (Entrainer) Influence of temperature

20. Data by: Gährs 1984 Ebeling, Franck 1984 Johannsen, Brunner 1994 Solubility of Caffeine in CO 2

21. Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment...... Modes For Product Recovery

22. Gährs 1984 Anti-Solvent: Solubility of Caffeine in CO 2 Influence of nitrogen

23. Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment...... Modes For Product Recovery

24. Solvent Cycle With Membrane Separation

25. GKSS-membrane (organic, active dense layer) CO 2 OC Permeate Retentate 1.86 wt.-% < 0.06 wt.-%  p = 2.0 MPa active dense layer 1.5 mole CO 2 kg/(m 2 h) P = 18 MPa, T = 323 K Separation by Membranes

26. Solvent Cycle in a T,s - Diagram Extraction/ separation Precipitationat high  p Precipitation at low  p Compressormode Entropy Temperature CO 2

27. 53 kJ/ kg CO2 21 kJ/ kg CO2 7.6 kJ/ kg CO2 Like in 2 Energy For Different Solvent Cycles Pump-Cycle Compressor-Cycle Membrane-Cycle Sartorelli 2001

28. Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment...... Modes For Product Recovery

29. Adsorption of Caffeine on Activated Carbon

30. Silica with 52% loading, loaded by high pressure adsorption Silica with 50% loading, loaded by mixing, conventional process Recovery of Tocopherolacetate by Adsorption

32. Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment...... Modes For Product Recovery

33. Phase Equilibrium Caffeine - Water - CO 2

34. Reduction of pressure or density Anti solvent Membrane separation Adsorption Absorption De-Entrainment...... Modes For Product Recovery

35. Brunner 1983 Solubility in a Gas With a Modifier (Entrainer) Influence of temperature

36. Birtigh De-Entrainment

37. Generalization of Precipitation: Membership - Functions Temperature at the Swimming Pool T [ o C]  x 253545 0 1  (x) (x) „Hot“ Not yet hot Too hot  (x): relative number of statements from people at the pool

38. Birtigh Membership Functions  P Adsorption Membrane

39. Absorption De-Entrain  T   T  Birtigh Membership Functions