1 / 41

Acetic Acid Separation Methods

Acetic Acid Separation Methods. Supervisore : Prof . H. S. Ghaziaskar By: H. Rastegari. Contents. Acetic Acid Uses Acetic Acid Production Acetic Acid Separation methods Conclusion References. Acetic Acid Uses. In vinyl acetate monomer production In acetic anhydride production

ratana
Télécharger la présentation

Acetic Acid Separation Methods

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Acetic Acid Separation Methods Supervisore: Prof. H. S. Ghaziaskar By: H. Rastegari

  2. Contents • Acetic Acid Uses • Acetic Acid Production • Acetic Acid Separation methods • Conclusion • References

  3. Acetic Acid Uses • In vinyl acetate monomer production • In acetic anhydride production • As solvent in production of terphetalic acid • As recrystalization solvent • In Silage • In production of various acetates such as: • Sodium acetate • Copper acetate • Aluminum acetate • Palladium acetate 2

  4. Acetic Acid Production • Chemical processes for acetic acid production: • Reaction of methanol with carbon monoxide • Reaction of acetylene with water followed by air oxidation • Fermentation of ethanol • Butane oxidation 3

  5. Other chemical processes which produce acetic acid • as a by-product: • Manufacture of cellulose esters • Reactions involving acetic anhydride • Synthesis of glyoxal from acetaldehyde and nitric acid • Wood distillate 4

  6. Problem • Separating acetic acid from water 5

  7. Separation Methods • Separation Involving Phase Changes: • Simple Distillation • Azeotropic Distillation • Extractive Distillation • Reactive Distillation • Separation involving membranes: • Pervaporation • Evapomeation • Temperature Difference Evapomeation • Electrodialysis • Bipolar Membrane Electrodialysis

  8. Simple Distillation • Physical separation process based on differences in volatilities 7

  9. Advantage • Simple and easy to operate • Disadvantage • Large energy consumption 8

  10. Azeotropic Distillation • Distillation in the presence of entrainer 9

  11. Desirable properties for an azeotropic entrainer : • Heterogeneous azeotrope • Commercially available and inexpensive • Nontoxic • Chemically Stable • Noncorrosive • Low heat of vaporization The best entrainer is: Alkyl Acetate 10

  12. Effective parameters for alkyl acetate selection • Azeotropic temperature • Azeotropic composition • Aqueous phase composition and entrainer pricing 11

  13. Advantage Improving the economics of the separation • Disadvantage Requiring large amount of entrainer 12

  14. Extractive Distillation • Distillation in the presence of solvent 13

  15. Desirable properties for solvent: • Nonvolatile • High boiling point • Make large difference in volatility between components • Miscible with mixture and doesn´t form azeotropic mixture • Commercially available and inexpensive • Noncorrosive • Physically and chemically stable 14

  16. The best solvent is: • Trialkyl Amine • Advantage Relatively little energy consumption • Disadvantage Need additional heat requirement on the column Some what larger plates 15

  17. Reactive Distillation • Chemical separation method which combines simultaneous chemical reaction and multicomponent distillation in the same vessel 16

  18. Mechanism of reaction: • First Step: Second Step: Third Step: 17

  19. Effect of various parameters on the acid conversion • Total feed flow rate Optimum value:192 mL/h • Mole ratio 18

  20. Reflux configuration • Feed position 19

  21. Pervaporation (PV) • separation of liquid mixtures by partial vaporization through membrane 20

  22. Used membrane • Polydimethylsiloxane (PDMS) • Cross-linked polybutadiene • Silicalite-1 as adsorbent filler in PDMS membrane • Carbon molecular sieve in PDMS membrane • Silicalite-1(pure silica) • Ge-ZSM-5 • Sn-ZSM-5 20

  23. Effective parameters on separation performance • Si/Sn • Temperature • Acid concentration • Disadvantage Shrinking and swelling of the membrane 21

  24. Evapomeation(EV) • Vaporization of feed solution then permeation through polymeric membrane 22

  25. Effective parameters on separation performance • Temperature • Acid concentration • Disadvantage membrane condensation in high acid concentration 23

  26. Temperature Difference Evapomeation (TDEV) • Decreasingtemperature in the membranesurroundingthaninthe feed solution 24

  27. Electrodialysis (ED) • Ion transportation from one solution through ion- exchange membranes to another solution under the influence of an electric potential difference 25

  28. Application Concentrating acetic acid from water containing %1(w/w) acid to %10(w/w) 26

  29. Importance Make full use of our limited resources Protect our environment • DisadvantageConcentration efficiency up to %10 Low electric current efficiency (around %20) 27

  30. Bipolar Membrane Electrodialysis (BME) 28

  31. Application Concentrating acetic acid from water containing %0.2(w/w) acid to %14(w/w) • Disadvantage Low electric current efficiency (around %40) 29

  32. Conclusion For high purity (%99.9) acetic acidAzeotropic Distillation For reasonably pure acetic acid Extractive Distillation For ester production Reactive Distillation For separation from solution containing % (5-15) acid PV 30

  33. References [1] Garwin,L., Hutchisoni,K., E., 1950. IndustrialAndEngineering Chemistry 42(4), 727-730. [2] Othmer, D., F., 1935. Industrial And Engineering Chemistry 27(3), 250-255. [3] Lee, F., M., Wytcherley, R., W., Distillation, Academic Press, USA, 2000. [4] Chien, I., L., Kuo, C., L., 2006. Chemical Engineering Science 61, 569-585. [5] Wang, S., J., Lee, C., J., Jang, S., S., Shieh, S., S., 2008. Process Control 18, 45-60.

  34. [6] Garwin, L., Haddad, P., O., 1953. Industrial And Engineering Chemistry 45(7), 1558-1562. [7] Lei, Z., Li, C., Li, Y., Chen, B., 2004. Separation And Purification Technology 36, 131-138. [8] Taylor, R., Krishna, R., 2000. Chemical Engineering Science 55, 5183- 5229. [9] Saha, B., Chopade, S., P., Mahajani, S., M., 2000. Catalysis Today 60, 147-157. [10] Yu, L., Guo, Q., Hao, J., Jiang, W., 2000. Desalination 129, 283-288. [11] Sun, W., Wang, X., Yang, J., Lu, J., Han, H., Zhang, Y., Wang, J., 2009. Membrane Science 335, 83-88.

  35. [12] Li, G., Kikuchi, E., Matsukata, M., 2003. Separation Purification Technology 32,199-206. [13] Toti, U., S., Kariduraganavar, M., Y., Soppimath, K., S., Aminabhavi, T., M., 2002. Applied Polymer Science 83, 259-272. [14] Asman, G., Anl, O., 2006. Separation Science And Technology 41(6) 1193-1209. [15] Asman, G., Sanli, O., 2006. Applied Polymer Science 100, 1385-1394. [16] Chien, I., L., Zeng, K., L., Chao, H., Y., Liu, J., H., 2004.Chemical Engineering Science 59, 4547-4567. [17] Kittur, A., A., Tambe, S., M., Kulkarni, S., S., Kariduraganavar, M., Y., 2004. Applied Polymer Science 94, 2101-2109.

  36. Thanks for your attention

  37. Acetic Acid Production Glyoxal:

  38. Simple Distillation VHAC= (yHAC) / (xHAC) VH2O= (yH2O) / (xH2O) Dalton's Law: PH2O= (yH2O) * pt Raoult's law: PH2O= (xH2O) * p0H2O

  39. α = VH2O / VHAC Fenske Equation: (yH2O)/(1- yH2O) = αn+1 (xH2O)/(1- xH2O)

  40. Azeotropic Distillation

  41. Extractive Distillation Solvent volume

More Related