Triacylglycerol purification by a continuous regenerable adsorbent process
The process utilizes the adsorbent column system as a treatment after chemical refining or before physical refining rather than water or filtration, respectively, to remove soaps and other impurities entrained in a crude triacylglycerol. The CDTAG or ORTAG is contacted with an adsorbent packed into a column, or multiple columns in series, for a sufficient amount of time to remove impurities such as, but not limited to, soaps, metals, chlorophyll, and many of the other compounds that reduce the stability of the TAG. The resulting TAG exiting the column(s) is ready for the deodorization process. Once the adsorbent no longer removes the desired amount of impurities, it is regenerated for reuse. Such a continuous regenerable adsorbent refining process substantially reduces the amount of fresh water required and the amount of waste water generated to purify TAG and reduces the amount of solid waste produced.
1. A process for purification of animal or vegetable oils comprising:
(a) treating crude triacylglycerol (TAG) utilizing one or more adsorbent columns containing an adsorbent material for removing one or more impurities from the crude TAG, said TAG continuously flows through said one or more columns;
(b) regenerating the adsorbent material with an acidic alcohol for removing adsorbed impurities from the adsorbent material; and
(c) reusing the adsorbent material in step (a),
wherein said impurities are comprised of one or more of phosphorus, soap, metals, free fatty acids (FFA), flavor compounds, odor compounds, color bodies, chlorophyll and other impurities that reduce the stability of finished TAG.
2. The process of claim 1 wherein said crude triacylglycerol is degummed (CDTAG).
3. The process of claim 1 wherein the adsorbent material is a powder, granulated, extruded, or otherwise processed to facilitate flow through the one or more columns.
4. The process of claim 1 wherein the adsorbent material is selected from carbon, silica, zeolite, metal silicate, metal oxide, bleaching clay, and acid activated bleaching clay.
5. The process of claim 1 wherein the adsorbent material is magnesium silicate.
6. The process of claim 1 wherein the adsorbent is synthetic magnesium silicate.
7. The process of claim 1 wherein the adsorbent is silica gel.
8. The process of claim 1 wherein the adsorbent is activated alumina.
9. The process of claim 1 wherein the adsorbent is bleaching clay.
10. The process of claim 1 wherein the adsorbent is acid activated bleaching clay.
11. The process of claim 1 wherein the regeneration of the adsorbent material is performed in a first step with a first solvent and a second step with a second solvent, wherein the second solvent is the acidic alcohol.
12. The process of claim 11 wherein said TAG absorbed in the adsorbent material removed from the adsorbent material in the first step with the first solvent.
13. The process of claim 12 wherein the first solvent is a non-polar solvent.
14. The process of claim 13 wherein the first solvent is hexane.
15. The process of claim 1 wherein the acid is sulfuric acid.
16. The process of claim 1 wherein the alcohol is ethanol.
17. The process of claim 1 wherein the alcohol is methanol.
18. The process of claim 12 wherein the first solvent is separated from a mixture of the first solvent and TAG removed from the adsorbent material during the regeneration, said first solvent is reclaimed for reuse and the TAG separated from the mixture of the first solvent and the TAG is further processed.
19. The process of claim 18 wherein the first solvent is separated from the mixture using distillation.
20. The process of claim 12 wherein the mixture of the first solvent and the TAG removed from the adsorbent during regeneration is recycled back upstream and mixed into a solvent and TAG mixture from oil extraction from an oil seed step.
21. The process of claim 12 wherein the first solvent is separated from a filtrate of the first solvent and TAG and, the first solvent is reclaimed for reuse.
22. The process of claim 21 the first solvent is separated from the filtrate of the first solvent and TAG using distillation.
23. The process of claim 22 wherein the TAG remaining after the first solvent is separated from the filtrate of the first solvent and TAG is further processed.
24. The process of claim 11 wherein the second solvent is separated from a filtrate of the second solvent and impurities from regeneration and the second solvent is reclaimed for reuse.
25. The process of claim 24 wherein the second solvent is separated from the impurities of the filtrate of the second solvent and impurities using distillation.
26. The process of claim 24 wherein the impurities remaining after the second solvent is separated from the filtrate of the second solvent and impurities is further processed or disposed of.
27. The process of claim 1 wherein the regeneration of the adsorbent material is performed in one step.
28. The process of claim 1 wherein the acidic alcohol is separated from a filtrate of the acidic alcohol, the TAG, and the impurities and the acidic alcohol is reclaimed for reuse.
29. The process of claim 28 wherein the acidic alcohol is separated from the filtrate of the acidic alcohol, the TAG, and the impurities using distillation.
30. The process of claim 28 wherein residual filtrate after separation of the acidic alcohol from the filtrate is recycled back upstream and blended with the crude TAG, and further comprising an alkaline neutralization step of the crude TAG.
31. The process of claim 30 wherein the crude TAG is separated from impurities by centrifugation.
32. The process of claim 31 wherein residual impurities are centrifuged out into soap stock.
33. The process of claim 1 wherein the acidic alcohol is entrained in TAG flowing from the regenerated column and is separated from the TAG and reclaimed for reuse.
34. The process of claim 33 wherein the separation of the solvent from the TAG is performed in a deodorization step.
35. The process of claim 33 wherein the separation of the solvent from the TAG is performed in by the step of evaporation of the solvent from the TAG prior to the deodorization step.
36. The process of claim 35 wherein the TAG is sent to a deodorization step of the process for purification of animal and vegetable oils.