Methods and apparatus for producing alkyl esters from lipid feed stocks, alcohol feedstocks, and acids

• US 10,696,923 B2
• Filed: 02/07/2019
• Issued: 06/30/2020
• Est. Priority Date: 02/07/2018
• Status: Active Grant

• Current Assignee: Sartec
• Original Assignee: Sartec
• Inventors: McNeff, Charles Vincent, McNeff, Clayton V., McNeff, Larry C., Yan, Bingwen
• Primary Examiner(s): Carr, Deborah D
• Application Number:
  US16/270,194
• Publication Number:
  US 20190241835A1
• Time in Patent Office: 509 Days
• Field of Search: 554169
• CPC Class Codes: B01J 21/04 Alumina
• CPC Class Codes: B01J 21/063 Titanium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 21/066 Zirconium or hafnium; Oxides or hydroxides thereof
• CPC Class Codes: C07C 51/15 by reaction of organic compounds with carbon dioxide, e.g. Kolbe-Schmitt synthesis
• CPC Class Codes: C07C 67/02 by interreacting ester groups, i.e. transesterification
• CPC Class Codes: C07C 67/03 by reacting an ester group with a hydroxy group
• CPC Class Codes: C07C 67/08 by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
• CPC Class Codes: C07C 69/52 Esters of acyclic unsaturated carboxylic acids having the esterified carboxyl group bound to an acyclic carbon atom
• CPC Class Codes: C11B 13/00 Recovery of fats, fatty oils or fatty acids from waste materials
• CPC Class Codes: C11C 1/002 Sources of fatty acids, e.g. natural glycerides, characterised by the nature, the quantities or the distribution of said acids
• CPC Class Codes: C11C 3/003 by esterification of fatty acids with alcohols C11C3/02 takes precedence
• CPC Class Codes: C11C 3/04 by esterification of fats or fatty oils
• CPC Class Codes: Y02P 20/54 using solvents, e.g. supercritical solvents or ionic liquids
• CPC Class Codes: Y02W 30/74 Recovery of fats, fatty oils, fatty acids or other fatty substances, e.g. lanolin or waxes

Abstract

Embodiments herein relate to the production of alkyl esters from lipid feed stocks. In an embodiment, a process for producing alkyl esters is included. The process can include mixing a lipid feed stock with an alcohol, water, and at least one of carbon dioxide, carbon monoxide, and/or one or more acids to form a reaction mixture, and contacting the reaction mixture with a catalyst under supercritical conditions for the alcohol, the catalyst comprising a metal oxide. Other embodiments are also included herein.

Claims

1. A process for producing alkyl esters comprising:

mixing a lipid feed stock with an alcohol, water and at least one of carbon dioxide and/or one or more acids to form a reaction mixture; and

contacting the reaction mixture with a catalyst under supercritical conditions for the alcohol,

the catalyst comprising a metal oxide; and

wherein an amount of alkyl esters is produced that is at least 10% by weight greater than that produced by an otherwise identical reaction mixture lacking the carbon dioxide and one or more acids under the same reaction conditions and residence time.

2. The process of claim 1, the metal oxide selected from the group consisting of alumina, titania, zirconia, and hafnia.

3. The process of claim 1, the lipid feed stock having an acid number of greater than or equal to 3 mg KOH/g oil.

4. The process of claim 3, wherein the step of contacting the reaction mixture with a catalyst comprises conversion of the lipid feed stock from an acid number of equal to 3 mg KOH/g oil to an acid number of less than or equal to 0.5 mg KOH/g oil.

5. The process of claim 1, the acid comprising an organic acid.

6. The process of claim 1, the acid comprising a Bronsted acid.

7. The process of claim 1, the acid comprising an inorganic acid.

8. The process of claim 1, further including mixing an inorganic base or an organic base into the reaction mixture.

9. The process of claim 1, wherein the step of contacting the reaction mixture with a catalyst is performed at a temperature of between 200 and 400 degrees Celsius.

10. The process of claim 1, wherein the step of contacting the reaction mixture with a catalyst is performed at a pressure of between 1000 and 5000 psi.

11. The process of claim 1, wherein the catalyst has a porosity of between 0.3 and 0.6.

12. The process of claim 1, wherein carbon dioxide is present in an amount equal to at least 0.1 wt. percent of the mass of the alcohol added.

13. The process of claim 1, wherein carbon dioxide is present in an amount equal to at least 0.5 wt. percent of the mass of the alcohol added.

14. The process of claim 1, the reaction mixture comprising carbonic acid at concentration of at least 0.05 M.

15. The process of claim 1, the reaction mixture comprising carbonic acid at concentration of at least 1 M.

16. The process of claim 1, wherein the pH of the reaction mixture is less than 7.

17. The process of claim 1, wherein the pH of the reaction mixture is less than 3.

18. A process for producing alkyl esters comprising:

mixing a lipid feed stock with an alcohol, water and at least one of carbon dioxide and/or one or more acids to form a reaction mixture; and

contacting the reaction mixture with a catalyst under supercritical conditions for the alcohol,

the catalyst comprising a metal oxide; and

wherein the catalyst comprises particles with an average particle size of 0.2 microns to 2 millimeters.

19. A process for producing alkyl esters comprising:

mixing a lipid feed stock with an alcohol, water and at least one of carbon dioxide and/or one or more acids to form a reaction mixture; and

contacting the reaction mixture with a catalyst under supercritical conditions for the alcohol,

the catalyst comprising a metal oxide; and

wherein the catalyst comprises a pore volume of between 0 and 0.6 ml/gram.