Sulfur-modified bitumen compositions

Patent metadata

Field	Value
Publication number	US-12415925-B2
Application number	US-202117565589-A
Country	US
Kind code	B2
Filing date	Dec 30, 2021
Priority date	Dec 30, 2020
Publication date	Sep 16, 2025
Grant date	Sep 16, 2025

Abstract

Preparing a modified bitumen composition includes combining bitumen with elemental sulfur to yield a mixture, and crystallizing the elemental sulfur on a surface of the bitumen to yield a layer of elemental sulfur on the surface of the bitumen. The mixture typically includes about 5 wt % to about 15 wt % of the elemental sulfur. A modified bitumen composition includes A modified bitumen composition includes bitumen and elemental sulfur on a surface of the bitumen. The modified bitumen composition includes about 5 wt % to about 15 wt % of the elemental sulfur.

First claim

What is claimed is:

1. A method of preparing a modified bitumen, the method comprising:
combining bitumen with elemental sulfur to yield a mixture, wherein the mixture comprises about 5 wt % to about 15 wt % of the elemental sulfur; and
crystallizing the elemental sulfur on a surface of the bitumen to yield a layer of elemental sulfur on the surface of the bitumen to yield the modified bitumen,
wherein crystallizing the elemental sulfur on a surface of the bitumen comprises heating the bitumen under pressure in a pressure aging vessel.

2. The method of claim 1 , wherein the mixture comprises about 10 wt % of the elemental sulfur.

3. The method of claim 1 , further comprising combining a bio-oil with the mixture.

4. The method of claim 3 , wherein the bio-oil comprises one or more of waste vegetable oil, wood pellet oil, corn stover oil, and miscanthus oil.

5. The method of claim 3 , wherein the bio-oil comprises polyaromatic molecules.

6. The method of claim 1 , wherein the rubberized bitumen comprises crumb rubber.

7. The method of claim 6 , wherein the crumb rubber comprises bio-treated crumb rubber.

8. The method of claim 7 , wherein the bio-treated crumb rubber comprises corn stover oil, castor oil, miscanthus oil, wood pellet oil, or waste vegetable oil.

9. The method of claim 1 , wherein the elemental sulfur on the surface of the bitumen comprises sulfur blooms.

10. The method of claim 9 , wherein the sulfur blooms comprise regions of microscale elemental sulfur crystals.

11. The method of claim 10 , wherein the regions comprise millimeter-sized patches.

12. The method of claim 1 , wherein the modified bitumen comprises amorphous elemental sulfur.

13. The method of claim 12 , wherein at least some of the amorphous elemental sulfur is beneath a surface of the modified bitumen.

14. The method of claim 1 , wherein the mixture consists of bitumen and elemental sulfur.

15. The method of claim 1 , wherein the mixture consists of bitumen, elemental sulfur, and bio-oil.

16. The method of claim 15 , wherein the bio-oil comprises waste vegetable oil, wood pellet oil, corn stover oil, or miscanthus oil.

17. The method of claim 16 , wherein the bio-oil comprises wood pellet bio-oil.

18. The method of claim 1 , wherein the mixture is free of stone aggregate.

19. The method of claim 1 , wherein the bitumen comprises rubberized bitumen.

Assignees

• Fini Elham
• Hung Albert
• Univ Arizona State

Inventors

• Fini Elham
• Hung Albert

Classifications

• C08L2555/54

  Sulfur or carbon black · CPC title

• C08L2555/64

  Oils, fats or waxes based upon fatty acid esters, e.g. fish oil, olive oil, lard, cocoa butter, bees wax or carnauba wax · CPC title

• C08L95/00 Primary

  Compositions of bituminous materials, e.g. asphalt, tar, pitch · CPC title