Cold treatment

Patent metadata

Field	Value
Publication number	US-12371633-B2
Application number	US-201716635680-A
Country	US
Kind code	B2
Filing date	Aug 1, 2017
Priority date	Aug 1, 2017
Publication date	Jul 29, 2025
Grant date	Jul 29, 2025

Abstract

The present invention relates to a new high-throughput process for reducing impurities in essential oils and extracts (in particular for fragrances, fragrance ingredients, flavours and cosmetic ingredients) under mild conditions. Undesirable natural components such as waxes, but also synthetic materials such as agrochemicals and other environmental pollutants are reduced by using at least one selective nanofiltration membrane. In addition, the present invention relates to a method for reducing coloured components in essential oils to obtain a less coloured or even colourless essential oil, while achieving high re-colouration stability over time. Further, the odour quality is maintained or increased through reduction of undesirable olfactory substances to achieve a purified and higher quality oil.

First claim

The invention claimed is:

1. A nanofiltration process for purifying an essential oil for a fragrance, flavour or cosmetic ingredient by removing synthetic pesticide or fungicide impurities, comprising the following steps:
(i) providing a selectively permeable thin film composite (TFC) nanofiltration membrane, wherein the membrane consists of a top layer and a more porous chemically different layer, wherein the top layer comprises a material selected from the group consisting of polyoctylmethylsiloxane, poly[1-(trimethylsilyl)-1-propyne], poly(2,6-dimethyl-1,4-phenylene oxide), polyacrylonitrile, polymer of intrinsic microporosity (PIM-1), polystyrene-b-poly(ethylene oxide) diblockcopolymer, poly(sodiumstyrenesulphonate) (PSS) or polyvinylsulphate (PVS) and mixtures thereof
and wherein the TFC nanofiltration membrane has a molecular weight cut-off of between 150 g/mol and 1200 g/mol;
(ii) providing a flowable input of essential oil, with a solvent component;
(iii) separating the flowable input by transferring it across the surface of the membrane to form a retentate and a permeate, such that the concentration of one or more components of the permeate is reduced compared to the flowable input; wherein the flow rate through the membrane is at least 8 kg [permeate]/h*m2 [membrane];
and wherein the permeate is decoloured in comparison to the flowable input, such that the lightness value L* of the permeate is increased in comparison to the flowable input to ΔL* greater than or equal to 1 and the chromaticity C* of the permeate is decreased in comparison to the flowable input to ΔC* less than or equal to −2, according to the CIELAB colour measurement system, as specified by the International Commission on Illumination;
(iv) collecting the permeate and removing the solvent.

2. The process according to claim 1 , wherein the lightness value L* of the permeate is increased in comparison to the flowable input to ΔL* greater than or equal to 1.5, and/or the chromaticity C* of the permeate is decreased in comparison to the flowable input to ΔC* less than or equal to −4.

3. The process according to claim 1 , wherein the colour stability of the permeate is such that the re-colouration measured by the change in lightness of the permeate 48 h after nanofiltration in comparison to the permeate just after nanofiltration is only decreased to ΔL* greater than or equal to −1.0, and/or the chromaticity C* of the permeate 48 h after nanofiltration is only increased in comparison to the permeate after nanofiltration to ΔC* less than or equal to 10.

4. The process according to claim 1 , wherein the more porous chemically different layer of the TFC nanofiltration membrane comprises a polymer which includes one or more of the heteroatoms O, N, S, and/or halogen, and/or Si.

5. The process according to claim 1 , wherein the more porous chemically different layer comprises a material chosen from the group consisting of: polydimethylsiloxane, polyoctylmethylsiloxane, poly[1-(trimethylsilyl)-1-propyne], polytetrafluoroethylene, polysulfone, polyethersulfone, polyvinylidene fluoride and polyetheretherketone.

6. The process according to claim 1 , wherein the solvent component comprises an organic solvent, and the organic solvent has a dipole moment of at least 4*10 −30 Cm.

7. The process according to claim 6 , wherein the organic solvent used to prepare the flowable input is chosen from the group consisting of: diethyl ether, ethanol, isopropanol, ethyl acetate, methylethylketone, butylacetat, methyl-tert-butyl-ether, cyclohexanol and acetone.

8. The process according to claim 7 , wherein the organic solvent used to prepare the flowable input is chosen from methyl-tert-butyl-ether and ethanol.

9. The process according to claim 1 , wherein the solvent further comprises a second organic solvent component, which has a dipole moment of less than 2*10 −30 Cm.

10. The process according to claim 9 , wherein the essential oil is chosen from the group consisting of: mandarine oil, peru balsam, tangerine oil, blood orange oil, patchouli oil, vanilla extract and benzoin siam oil.

11. The process according to claim 1 , wherein the essential oil is derived from the genus Citrus.

12. The process according to claim 1 , wherein the lightness value L* of the permeate is increased in comparison to the flowable input to ΔL* greater than or equal to 2.0, and/or the chromaticity C* of the permeate is decreased in comparison to the flowable input to ΔC* less than or equal to −10.

13. The process according to claim 1 , wherein the essential oil is chosen from the group consisting of: sweet orange, orange, lemon, lime, grapefruit, bergamot, key lime, pomelo, citron, mandarine, tangerine, bitter orange, blood orange and/or wherein the essential oil is selected from the group consisting of: peru balsam oil, benzoin siam oil, patchouli oil, rose oil, ylang oil, clove leaves, lemon oil, oak moss absolute and vanilla extract.

14. A system for performing the nanofiltration process for the purification of essential oils according to claim 1 , comprising the selectively permeable thin film composite (TFC) nanofiltration membrane with the more porous chemically different layer and the top layer, wherein the TFC nanofiltration membrane comprises a polymer, which includes one or more heteroatom selected from O, N, S, and/or halogen and/or Si; wherein the top layer comprises a material selected from the group consisting of polyoctylmethylsiloxane, poly[1-(trimethylsilyl)-1-propyne], poly(2,6-dimethyl-1,4-phenylene oxide), polyacrylonitrile, polymer of intrinsic microporosity (PIM-1), polystyrene-b-poly(ethylene oxide) diblockcopolymer, poly(sodiumstyrenesulphonate) (PSS) or polyvinylsulphate (PVS) and mixtures thereof; a flowable input of essential oil; wherein the flow rate of the flowable input through the first membrane is at least 8 kg [permeate]/h*m 2 [membrane]; and wherein the TFC nanofiltration membrane has a molecular weight cut off between 150 g/mol and 1200 g/mol.

Assignees

• Symrise Ag

Inventors

• Chandrasekaran Vijayanand
• Brennecke Stefan
• Schaar Uwe
• Diaz Gomez Edison
• Utermöhle Claudia
• Kurzenne Pierre

Classifications

• B01D69/1218

  Layers having the same chemical composition, but different properties, e.g. pore size, molecular weight or porosity · CPC title

• B01D71/701

  Polydimethylsiloxane · CPC title

• B01D69/107

  Organic support material · CPC title

• B01D2325/20

  Specific permeability or cut-off range · CPC title

• B01D69/02

  characterised by their properties · CPC title