Direct transesterification of algal biomass for synthesis of fatty acid ethyl esters (FAEE)

Patent metadata

Field	Value
Publication number	US-9416336-B2
Application number	US-201514877121-A
Country	US
Kind code	B2
Filing date	Oct 7, 2015
Priority date	Mar 15, 2013
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

Methods of producing fatty acid ethyl esters (FAEE) using a direct transesterification process are described. The direct transesterification process uses low levels of chemical solvents, acid catalysts, and heating energy to produce the FAEE in a method with increased efficiency in a co-solvent system. The FAEE produced may be used in a variety of products including health, beauty, nutraceutical, and cosmetic products.

First claim

What is claimed is:

1. A method for recovering fatty acid ethyl esters (FAEE) from microalgae, comprising:
a. mixing microalgae comprising lipids and biomass with a first non-polar solvent at a biomass:first non-polar solvent ratio of 1:1 to 1:10 to form a first reaction mixture;
b. mixing the first reaction mixture with ethanol and a liquid acid catalyst to generate a second reaction mixture at a biomass:catalyst ratio of 1:0.1 to 1:2 and a biomass:ethanol ratio of 1:1 to 1:10;
c. heating the second reaction mixture to generate an ester mixture comprising at least some of the lipids converted into an FAEE product;
d. contacting the ester mixture with a second non-polar solvent to generate a first extraction mixture;
e. separating the first extraction mixture into a first liquid fraction comprising the FAEE product and a solid fraction comprising biomass; and
f. recovering the FAEE product in the first liquid fraction at an actual yield of at least 69%.

2. The method of claim 1 , wherein the second reaction mixture is heated to a temperature of 50-75° C. for a period of 4-8 hours.

3. The method of claim 2 , further comprising cooling the ester mixture to 30-50° C.

4. The method of claim 3 , further comprising neutralizing the ester mixture with a weak base.

5. The method of claim 4 , wherein the weak base is water.

6. The method of claim 1 , wherein the microalgae is dried microalgae.

7. The method of claim 1 , wherein the microalgae comprises at least one species selected from the genera consisting of Schizochytrium and Nannochloropsis.

8. The method of claim 7 , wherein the Nannochloropsis biomass comprises biomass that was harvested in the oil accumulation phase.

9. The method of claim 1 , wherein the first non-polar solvent comprises at least one selected from the group consisting of hydrocarbons, halogenated hydrocarbons, hexane, heptane, octane, petroleum ether, chloroform, and supercritical carbon dioxide.

10. The method of claim 1 , wherein the second non-polar solvent comprises at least one selected from the group consisting of hydrocarbons, halogenated hydrocarbons, hexane, heptane, octane, petroleum ether, chloroform, and supercritical carbon dioxide.

11. The method of claim 1 , wherein the first and second non-polar solvent are the same.

12. The method of claim 1 , wherein the first and second non-polar solvent are different.

13. The method of claim 1 , wherein the liquid acid catalyst comprises at least one selected from the group consisting of hydrochloric acid (HCl), boron trifluoride (BF 3 ), phosphoric acid (H 3 PO 4 ), nitric acid, sulfuric acid, and organic sulfonic acid.

14. The method of claim 1 , wherein the separation of the first extraction mixture comprises at least one from the group consisting of filtration, membrane filtration, and centrifugation.

15. The method of claim 1 , further comprising fractionating the FAEE product into a saturated FAEE product and an unsaturated FAEE product.

16. The method of claim 15 , wherein the fractionating is performed by urea crystallization.

17. The method of claim 1 , further comprising fractionating the FAEE product into different length FAEE.

18. The method of claim 17 , wherein the fractionating is performed by molecular distillation.

19. The method of claim 17 , wherein at least one fraction is selected from the group consisting of an FAEE fraction having a fatty acid carbon chain of 16 or less, an Omega-7 FAEE fraction, an Omega-9 FAEE fraction, and an Omega-3 FAEE fraction.

20. The method of claim 1 , further comprising fractionating the FAEE production into different boiling point FAEE fractions.

Assignees

• Heliae Dev Llc

Inventors

• Shinde Sandip

Classifications

• C11C3/10

  Ester interchange · CPC title

• C11C1/08

  Refining · CPC title

• C11B3/12

  by distillation · CPC title

• C11C1/10 Primary

  by distillation · CPC title

• C11B3/04 Primary

  with acids · CPC title