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RU-2023123085-A - CHEMICAL SEPARATION OF SYNTHETIC FIBERS FROM A MIXTURE OF SYNTHETIC FIBERS AND SEMI-SYNTHETIC OR NATURAL FIBERS

RU2023123085ARU 2023123085 ARU2023123085 ARU 2023123085ARU-2023123085-A

Inventors

  • ФРЮ, Расселл Дэвид

Assignees

  • ОРИТЭЙН ГЛОБАЛ ЛИМИТЕД

Dates

Publication Date
20260508
Application Date
20220302
Priority Date
20210303

Claims (20)

  1. 1. A method for determining the origin of a material comprising a mixture of synthetic fibres and natural or semi-synthetic fibres, wherein the method comprises the following steps:
  2. a. contacting a sample of the material with a solution of an extracting agent to form a solution or suspension comprising i) synthetic fibres and fragments of synthetic fibres and ii) a solid residue containing natural or semi-synthetic fibres;
  3. b. separating the solution or suspension obtained in step a. from the solid residue;
  4. c. drying the solid residue;
  5. d. determining the ratios of isotopes of one or more of the following elements: carbon, oxygen, hydrogen, nitrogen, sulfur and strontium in the solid residue and/or determining the concentrations of one or more elements contained in trace amounts in the solid residue; and
  6. e. comparing the isotope ratios and/or concentrations determined in step d. with data obtained for natural or semi-synthetic fibres of known origin to determine the origin of the material.
  7. 2. The method according to claim 1, wherein the natural fibers are cotton, wool, fur, silk, hemp, flax or jute fibers.
  8. 3. The method according to claim 2, wherein the wool is obtained from a sheep, goat or alpaca.
  9. 4. The method according to claim 2, wherein the fur is obtained from rabbits or opossums.
  10. 5. The method according to any one of claims 1 to 4, wherein the semi-synthetic fibres are viscose, modal, rayon, acetate silk, lyocell or cupro fibres.
  11. 6. The method according to any one of claims 1 to 5, wherein the synthetic fibers are polyester, nylon, elastane or acrylic fibers.
  12. 7. The method according to any one of claims 1 to 6, wherein, prior to contact with the solution of the extracting agent in step a, the sample of material is ground to achieve an average particle size of approximately 50 to 250 μm.
  13. 8. The method according to any one of claims 1 to 7, wherein the solution of the extracting agent is acetone, ethanol, dimethylformamide (DMF), phenol, dichloromethane (DCM), formic acid, aqueous hydrochloric acid, aqueous sodium hydroxide, or any combination thereof.
  14. 9. The method according to any one of claims 1 to 8, wherein step a. comprises one or more cycles of i) stirring the sample in a solution of the extracting agent, ii) centrifuging the sample in the solution of the extracting agent, and iii) separating the solution from the solid residue.
  15. 10. The method of claim 9, further comprising one or more steps of heating the sample at a temperature ranging from 50 to 90°C.
  16. 11. The method according to any one of claims 1 to 10, wherein the solution obtained in step a. is separated from the solid residue by decantation, filtration or aspiration.
  17. 12. The method of claim 1, wherein the synthetic fiber is a polyester and the extracting agent solution is phenol in DCM (20% v/v) or aqueous sodium hydroxide (10% w/v).
  18. 13. The method according to claim 1, wherein the synthetic fiber is elastane and the solution of the extracting agent is ethanol in DMF (10% v/v).
  19. 14. The method of claim 1, wherein the synthetic fiber is nylon and the extracting agent solution is aqueous hydrochloric acid (18% w/v) or formic acid (98% v/v).
  20. 15. The method of claim 1, wherein the synthetic fiber is a polyester and the extracting agent solution is aqueous sodium hydroxide (10% w/v).