Green diesel production from hydrothermal catalytic decarboxylation on a supported Pd—Co catalyst

Patent metadata

Field	Value
Publication number	US-9790435-B2
Application number	US-201514744590-A
Country	US
Kind code	B2
Filing date	Jun 19, 2015
Priority date	Jun 20, 2014
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

Materials and methods for converting brown grease to useful diesel fuel are described. One material is a palladium catalyst on a silicon/carbon support. A method comprises flowing fresh hydrogen over a reaction of diluted brown grease on a palladium/carbon catalyst.

First claim

What is claimed is:

1. A catalyst for decarboxylation of a fatty acid, the catalyst comprising:
about 0.5% to about 10% palladium by weight; and
a support comprising silicon atoms and carbon atoms, a ratio of carbon atoms to silicon atoms of the support being about 3:1 to about 40:1.

2. The catalyst according to claim 1 , wherein the ratio of carbon atoms to silicon atoms is about 4.3:1 to about 34.7:1.

3. The catalyst according to claim 2 wherein the ratio of carbon atoms to silicon atoms is about 4.3:1.

4. The catalyst according to claim 1 having a porous surface with an average pore diameter of about 3.6 nanometers to about 5.4 nanometers.

5. The catalyst according to claim 1 comprising about 5% palladium by weight.

6. The catalyst according to claim 1 wherein the palladium comprises a metal particle having a diameter of about 3 nanometers to about 8 nanometers.

7. The catalyst according to claim 1 wherein the catalyst has an acidity of about 0.10 to about 2.5 mmol/gcat.

8. The catalyst according to claim 1 wherein when exposed to oleic acid, the catalyst converts at least 10% of the oleic acid to n-heptadecane.

9. The catalyst according to claim 8 which converts at least 30% of the oleic acid to n-heptadecane.

10. A method of making a catalyst for decarboxylation of a fatty acid, the method comprising:
combining activated carbon with tetraethyl orthosilicate to form a support, a ratio of carbon atoms to silicon atoms of the support being about 3:1 to about 40:1;
mixing a palladium solution with the support to result in the catalyst finally comprising about 0.5% to about 10% palladium by weight; and
drying the catalyst.

11. The method of claim 10 wherein the tetraethyl orthosilicate is provided in a mass ratio to the activated carbon of about 0.5:1 to about 4:1.

12. The method of claim 11 wherein the mass ratio of tetraethyl orthosilicate to activated carbon is about 4:1.

13. The method of claim 10 wherein palladium comprises about 5% of a weight of the catalyst.

14. The method of claim 10 wherein the palladium solution is a solution of about 1.1% palladium chloride by weight and a weight ratio of palladium chloride to support is about 0.088:1.

15. The method of claim 10 wherein when the catalyst is exposed to oleic acid, it converts at least 10% of the oleic acid to n-heptadecane.

16. A method of converting brown grease to green diesel, the method comprising:
diluting the brown grease with a diluent;
combining brown grease with a catalyst comprising about 0.5% to about 10% palladium by weight on a support comprising silicon atoms and carbon atoms in a reactor having a gas flow intake and a gas relief valve, a ratio of carbon atoms to silicon atoms of the support being about 3:1 to about 40:1; and
providing a volume of gas comprising hydrogen gas through the gas flow intake and allowing gas to exhaust through the gas relief valve to maintain a pressure of about 1.5 megapascal.

17. The method of claim 16 further comprising pretreating the brown grease with a catalyst comprising palladium and carbon under a flow of hydrogen gas.

18. The method of claim 17 wherein pretreating comprises about two hours at about one hundred degrees Celsius at a pressure of 1.5 megapascal.

19. The method of claim 16 wherein the catalyst is soaked with dodecane and reduced under a flow of hydrogen gas prior to combining with brown grease.

Assignees

• Univ Wayne State

Inventors

• Sari Elvan
• Salley Steven O
• Ng K Y Simon

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/10

  Infrared [IR] · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/80

  characterised by their amorphous structures · CPC title

• Y02P30/20

  using bio-feedstock · CPC title