WO2024058963A1

WO2024058963A1 - Rejuvenator for an asphalt pavement that leaves the surface black for an extended period of time

Info

Publication number: WO2024058963A1
Application number: PCT/US2023/032145
Authority: WO
Inventors: Marvin Keller Exline; Dan SWIERTZ; Douglas KRIECH
Original assignee: Heritage Research Group, Llc
Priority date: 2022-09-12
Filing date: 2023-09-07
Publication date: 2024-03-21

Abstract

Asphalt rejuvenator compositions comprising of water, at least one emulsifier, an oil, and gilsonite are disclosed. Disclosed compositions may have similar functionality of other asphalt rejuvenators but with the addition of gilsonite and an extended black or darker appearance after application to asphalt pavement.

Description

REJUVENATOR FOR AN ASPHALT PAVEMENT THAT LEAVES THE SURFACE BLACK FOR AN EXTENDED PERIOD OF TIME

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of US Provisional Application No. 63/375,291 filed September 12, 2022, which is hereby incorporated herein by reference in its entirety.

BACKGROUND

Asphalt rejuvenators can be either petroleum or plant-based products that help restore and preserve aged pavement surfaces. Asphalt pavements deteriorate over time from environmental exposure, air, and water related damage. Asphalt can become brittle and susceptible to cracking due to the expansion and contraction related to temperature change. Initially, asphalt pavement is black in color but in a short amount of time, usually less than a year, it starts to become gray in color.

Asphalt rejuvenators have historically been petroleum-based, primarily aromatic oils. These have been made into emulsions for ease of handling and better control of application rate. In the last decade, plant-based oils have been introduced into the market for use as rejuvenators for asphalt pavements. The plant-based products are handled in the same way as the petroleum-based oils and made into emulsions for end use. The plant-based products have been accepted by the end consumer as an equivalent to the petroleum-based products.

Pavements treated with rejuvenators will darken initially from oil-based emulsion reacting and softening the existing aged asphalt. The dark to black appearance is associated by the traveling public as a “new” pavement. Rejuvenating oil, either petroleum-based or biobased, have been blended with asphalt to create different grades of rejuvenating products. The asphalt/rejuvenator combination emulsions will give the pavement an initial darker appearance than the all oil-based rejuvenator. However, the asphalt/rejuvenator will age over time and revert to the same grey color as before the pavement was treated within 1-2 seasons after application.

Therefore, there remains a need for compositions and method for making the same which have the benefits of asphalt rejuvenators but with an extended black surface appearance. SUMMARY

In some embodiments, compositions are disclosed which have the functionality of asphalt rejuvenators but with an extended time period for black appearance after application.

In some embodiments, a composition comprising water, at least one emulsifier, a base oil, and gilsonite is disclosed.

In certain embodiments a method of rejuvenating an asphalt surface, comprising identifying of an asphalt surface; and applying a composition is disclosed. In further embodiments, the composition is spray-applied, broom-applied, to the asphalt surface.

Additional embodiments of the invention, as well as features and advantages thereof, will be apparent from the descriptions herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a digital image of an asphalt pavement before treatment with a rejuvenator.

Figure 2 shows a digital image of an asphalt pavement one day after application of a petroleum-based oil on left and 50:50 blend petroleum-based oil and asphalt on right.

Figure 3 shows a digital image of an asphalt pavement one year after application of a petroleum-based oil on left and 50:50 blend petroleum-based oil and asphalt on right.

Figure 4 shows a digital image of oil adjacent to a 90:10 blend of Oil/Gilsonite comprised of 60% Oil/Gilsonite blend at 90:10 proportioning and 40% water containing 1.2 % E-7000 based on total weight of emulsion and 0.2% liquid caustic.

Figure 5 shows a digital image of Portland cement concrete with application of oil emulsion residue on left and Oil/Gilsonite emulsion residue on right with image.

Figure 6 shows a digital image of Portland cement concrete with application of oil emulsion residue on left and Oil/Gilsonite emulsion residue on right with image. Figure 7 shows a graph of pavement lightness over time.

Figure 8 shows a graph of pavement lightness over time.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to certain embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications, and such further applications of the principles of the invention as described herein being contemplated as would normally occur to one skilled in the art to which the invention relates. Additionally, in the detailed description below, numerous alternatives are given for various features. It will be understood that each such disclosed alternative, or combinations of such alternatives, can be combined with the more generalized features discussed in the Summary above, or set forth in the embodiments described below to provide additional disclosed embodiments herein.

In certain embodiments, compositions of the present disclosure comprise of water, at least one emulsifier, a base oil, and gilsonite. Gilsonite is a natural product found in Utah. It is a resinous rock containing hydrocarbon materials. It is sold in the form of a powder and can be processed into a liquid format. Gilsonite is used in different industries for its bonding characteristics, UV stability, and fade resistant color.

Gilsonite may be processed in petroleum-based or plant-based oils to create a liquid product. For example, 10% Gilsonite can be placed in Cargill 1815 soy-based bio-oil. At ambient temperature a portion of the Gilsonite appears to dissolve. At an increased temperature of 240°F a substantial portion of the gilsonite appears to be incorporated into the oil.

In some embodiments the present disclosure may comprise of an emulsion, hi some embodiments the composition may comprise of an oil-in-water emulsion.

In some embodiments the composition may comprise gilsonite of about 0.01 to about 60 wt. %. Other compositions may comprise of about 0.1 to about 10 wt. % or about 0.5 to about 5 wt. % gilsonite.

In some embodiments the composition comprises base oil from about 1 to about 75 wt. %. Other compositions may comprise oil of about 5 to about 50 wt. % or 15 to about 30 wt. %. In some embodiments the base oil comprises a petroleum-based oil or a bio-based oil. In embodiments using bio-based oil, vegetable oil may be used in the composition. In some embodiments, a vegetable oil may comprise a soybean oil, more specifically an epoxidized soybean oil. In some embodiments, the oil is selected from a triglyceride, a diglyceride, a monoglyceride, and combinations thereof. In some embodiments, the oil comprises a synthetic or semi-synthetic oil, such as an estolide ester or alkyl esters of naturally-occurring hydroxylated fatty acids. Exemplary estolides include, but are not limited to, those disclosed in U.S. Patent No. 9,650,328, which is incorporated herein by reference in its entirety for all purposes. Exemplary hydroxylated fatty acid esters include, but are not limited to, C9-C20 hydroxylated fatty acid esters, such as methyl ricinoleate and methyl 12-hydroxystearate.

In some embodiments the composition comprises at least one emulsifier selected from a cationic or an anionic emulsifier. In some embodiments the at least one emulsifier is selected from a tall oil-based carboxylate and an alkyl amine.

It has been shown that compositions containing gilsonite leave a black appearance after application on concrete in comparison to similar composition without gilsonite as seen in Fig. 5 and Fig. 6. Due to the nature of gilsonite, it is expected to remain black for an extended period of time.

In some embodiments the method of rejuvenating an asphalt surface comprises of identification of an asphalt surface and application of a composition of Oil/Gilsonite blend. The composition may be spray-applied or broom-applied. In some embodiments the composition may be applied at a rate of about 0.01 to about 1 gallon per square yard (gal/SY). In other embodiments the composition is applied at a rate of about 0.01 to about 0.5 gal/SY or about 0.05 to 0. 1 gal/SY.

In some embodiments, a benefit of the emulsions described herein includes enhancement of the dark/black surface color of an existing asphalt surface. In some embodiments, the emulsions described herein will result in a black residue left on the surface of the existing surface after breaking of the emulsion and evaporation of the water. In some embodiments, the newly blackened surface can be measured/quantified using a color scanning device, such as a Color Muse SE device produced by Variable^{1 M}, which can quantify color by providing the relevant L-Value (L*) for the scanned surface. “L*” is a measurement of lightness/darkness, having a range of 0 (pure black) to 100 (pure white).

In some embodiments, treating an existing asphalt surface with a composition comprising the Gilsonite/base oil residue will increase the L* of the existing surface by at least 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or even 50%. For example, in some embodiments the existing asphalt/pavement surface will initially exhibit an L* of about 45. Subsequent to treatment, the Gilsonite/base oil can decrease the L* of the surface to about 28, which represents an increase in darkness of about 37%. In some embodiments, the asphalt/pavement surface will maintain a post-treatment L* value that is greater than the pretreatment value for at least 1, 2, or even 3 years. In some embodiments, the asphalt/pavement surface will maintain a post-treatment L* value that is greater than the pre-treatment value for about 1 to about 5 years.

In some embodiments, emulsions containing Gilsonite can be unstable and result in settling after longer periods of time. It has been surprisingly discovered that, in some embodiments, the stability of the Gilsonite emulsion can be enhanced by creating a Gilsonite “cutback” via the pre-digestion of Gilsonite in a solvent. This Gilsonite cutback can then be blended with the desired base oil to form a Gilsonite cutback/oil blend, which can be subsequently be emulsified with the desired water/ emulsifier combination. Thus, in certain embodiments, Applicant has surprisi ngly discovered a method of creating a Gilsonite cutback, wherein the cutback comprises a homogenous liquid mixture of gilsonite and the solvent.

Solvents for creating the Gilsonite cutback may include petroleum or biobased components. Exemplary cutback solvents include, but are not limited to, fatty acid monoesters (e.g., unsubstituted alkyl esters of C9-C20 fatty acids such as methyl soyate) and hydrocarbons (e.g., C9-C20 hydrocarbons such as #2 fuel oil). In certain embodiments, the solvents may also include any of the estolide esters and/or hydroxylated fatty acid esters described previously herein.

Accordingly, in certain embodiments the base material comprises a Gilsonite cutback and a base oil. In certain embodiments, the Gilsonite cutback comprises Gilsonite and a solvent. In certain embodiments, the base oil and the solvent comprise different materials. In certain embodiments, the Gilsonite cutback'base oil blend is emulsified in water with the desired emulsifier.

In order to promote a further understanding of the present invention and its various embodiments, the following specific examples are provided. It will be understood that these examples are illustrative and not limiting of the invention.

EXAMPLE 1

Preparation of Composition Comprising

Oil and Gilsonite

Materials and Methods:

10 % gilsonite powder was placed in in Cargill 1815 soy-based bio-oil. A portion of the Gilsonite appeared to dissolve in the oil at ambient temperature. The temperature of the oil was increased to 240°F and a substantial portion of the Gilsonite appeared to be incorporated into the oil. The 90:10 blend of Oil/Gilsonite was then further processed into an emulsion. The emulsion was comprised of 60% Oil/Gilsonite blend at 90:10 proportioning and 40% water containing 1 .2% E-7000 based on total weight of emulsion and 0.2% liquid caustic.

EXAMPLE 2

Application of Composition Comprising Oil and Gilsonite to Portland Cement

Materials and Methods:

The Oil/Gilsonite emulsion prepared in according to Example 1 was spread on some existing Portland cement concrete and a similar emulsion using the same oil but without Gilsonite was placed for comparison. The emulsions were then allowed to cure.

Results:

Visual color comparison was made. The Gilsonite-modified oil emulsion was black in appearance. Fig. 5 and fig. 6 present the appearance of the concrete for the visual comparisons.

EXAMPLE 3

Formation of Gilsonite Cutback, Cutback Base-Oil Blend, and Emulsion

Materials and Methods:

50 % by weight gilsonite powder was placed in either diesel fuel or methyl soyate (“biodiesel”) or a combination thereof. The mixture is heated to approximately 350 °F under continuous low shear mixing. The mixture is held at the referenced temperature for approximately 2 hours as the gilsonite completely incorporates into the liquid medium and a smooth appearance is noted, creating a gilsonite cutback. This resulting gilsonite cutback was further processed into emulsion base containing 10 % gilsonite by adjusting the temperature of the cutback to approximately 175 °F and preheating Cargill 1815 soy-based bio-oil to the same approximate temperature. The two parts are mixed at a weight ratio of 80% Cargill 1815 soybased bio-oil to 20% gilsonite cutback under low shear mixing until smooth appearance is achieved. The emulsion base at approximately 175 °F is further processed into emulsion comprised of 60% of the aforementioned emulsion base and 40% water containing 2.5% Indulin SBT-50 and 0.5% Redicote E-95 based on total weight of emulsion.

The produced emulsion is further diluted with water to a total residue content of 30 wt. % before application to a pavement surface. The resulting composition was applied at a rate of 0.058 gal/square yard (SY) to an asphalt surface having a pre-application L* value of about 45. The L* value (y-axis) was measured prior to application, immediately after application (Day 1), and at several points after application. These results are reported in Figure 7, as compared to a control emulsion-based rejuvenator without gilsonite (soybean-based rejuvenator Anova 1815, 30 wt. % residue) in Figure 8. The results indicate that a rejuvenator containing gilsonite can retain a much darker profile when compared to the control rejuvenator. For example, the gilsonite rejuvenator provides for an asphalt surface having an L* value that is still below 35 after 34 days, while the control in Figure 2 has the L* value dramatically increase to a level greater than 40 after 34 days.

The uses of the terms "a" and "an" and "the" and similar references in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-cl aimed element as essential to the practice of the invention.

While the invention has been illustrated and described in detail in the drawings and the foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. In addition, all references cited herein are indicative of the level of skill in the art and are hereby incorporated by reference in their entirety.

EMBODIMENTS

The following provides an enumerated listing of some of the embodiments disclosed herein. It will be understood that this listing is non-limiting, and that individual features or combinations of features (e.g. 2, 3 or 4 features) as described in the Detailed Description above can be incorporated with the below-listed Embodiments to provide additional disclosed embodiments herein.

1. A composition comprising: water; at least one emulsifier; an oil; and gilsonite.

2. The composition of embodiment 1, wherein the composition comprises an emulsion.

3. The composition of any one of embodiments 1 and 2, wherein the composition comprises an oil-in-water emulsion.

4. The composition of any of the preceding embodiments, wherein the gilsonite comprises about 0.01 to about 60 wt. % of the composition.

5. The composition of embodiment 4, wherein the gilsonite comprises about 0.1 to about 10 wt. % of the composition.

6. The composition of embodiment 4, wherein the gilsonite comprises about 0.5 to about 5 wt. % of the composition.

7. The composition of any one of the preceding embodiments, wherein the oil comprises about 1 to about 75 wt. % of the composition.

8. The composition of any one of the preceding embodiments, wherein the oil comprises about 5 to about 50 wt. % of the composition.

9 The composition of any one of the preceding embodiments, wherein the oil comprises about 15 to about 30 wt. % of the composition.

10. The composition of any one of the preceding embodiments, wherein the oil comprises a petroleum-based oil or a bio-based oil.

11. The composition of any one of the preceding embodiments, wherein the oil comprises a bio-based oil.

12. The composition of embodiment 11, wherein the bio-based oil comprises vegetable oil. 13. The composition of embodiment 12, wherein the vegetable oil comprises a soybean oil.

14. The composition of embodiment 13, wherein the soybean oil is an epoxidized soybean oil.

15. The composition of any one of the preceding embodiments, wherein the at least one emulsifier is selected from a cationic emulsifier and an anionic emulsifier.

16. The composition of any one of the preceding embodiments, wherein the at least one emulsifier is selected from a tall oil-based carboxylate and an alkyl amine.

17. A method of rejuvenating an asphalt surface, comprising: identifying an asphalt surface; and applying a composition of any of the preceding embodiments to the asphalt surface.

18. The method of embodiment 17, wherein the composition is spray-applied, broom- applied, to the asphalt surface.

19. The method of any one of embodiments 17-18, wherein the composition is applied at a rate of about 0.01 to about 1 gallon per square yard (gal/SY).

20. The method of embodiment 19, wherein the composition is applied at a rate of about 0.01 to about 0.5 gal/SY.

21. The method of embodiment 19, wherein the composition is applied at a rate of about 0.05 to about 0.1 gal/SY.

22. The composition of any one of embodiments 1-16, wherein the composition consists of the recited components.

23. The composition of any one of embodiments 1 -16, wherein the composition consists essentially of the recited components.

24. A composition comprising a gilsonite cutback; and a base oil.

25. The composition of embodiment 24, wherein the gilsonite cutback comprises gilsonite and a solvent

26. The composition of embodiment 25, wherein the solvent comprises at least one of a hydroxylated fatty acid alkyl ester, an unsubstituted fatty acid alkyl ester or a hydrocarbon. 27. The composition of embodiment 26, wherein the solvent comprises at least one of a C9-C20 hydroxylated fatty acid alkyl ester, an unsubstituted C9-C20 fatty acid alkyl ester or a C9-C20 hydrocarbon.

28. The composition of any of embodiments 24-27, wherein the base oil comprises a biobased oil.

29. The composition of any of embodiments 24-28, wherein the base oil comprises a triglyceride.

30. A method comprising: digesting gilsonite in a solvent to form a gilsonite cutback; and blending the gilsonite cutback in a base oil to form a gilsonite base.

31. The method of embodiment 30, further comprising blending the gilsonite base in water with an emulsifier to form a gilsonite-containing emulsion.

31. A method comprising: selecting a surface exhibiting an initial L* value of about 25 to about 60 when measured using a Color Muse SE device; and applying a composition comprising gilsonite and a base oil to the surface to provide a modified surface, wherein the modified surface exhibits an L* value that is at least 25% lower than the initial L* value.

32. The method of embodiment 31, wherein the modified surface exhibits an L* value that is at least 30% lower than the initial L* value.

33. The method of any of embodiments 31-32, wherein the initial L* value is about 35 to about 55.

34. The method of embodiment 33, wherein the initial L* value is about 40 to about 50.

34. The method of any of embodiments 31-33, wherein the modified surface exhibits an L * value of about 20 to about 40.

35. The method of embodiment 34, wherein the modified surface exhibits an L* value of about 25 to about 35.

36. The method of embodiment 35, wherein the modified surface exhibits an L* value of about 25 to about 35 for at least 30 days following application.

37. The method of embodiment 35, wherein the modified surface exhibits an L* value of about 25 to about 35 for about 30 to about 180 days.

38. A composition comprising a homogenous mixture of gilsonite and a solvent. 39. The composition of embodiment 38, wherein the solvent is selected from at least one of a one of a hydroxylated fatty acid alkyl ester, an unsubstituted fatty acid alkyl ester or a hydrocarbon.

40. The composition of embodiment 39, wherein the solvent comprises at least one of a C9-C20 hydroxylated fatty acid alkyl ester, an unsubstituted C9-C20 fatty acid alkyl ester or a C9-C20 hydrocarbon.

41. The composition according to any one of embodiments 1-9, wherein the oil is selected from at least one of an estolide ester or a hydroxylated fatty acid alkyl ester.

Claims

CLAIMS What is claimed is:

2. The composition of claim 1, wherein the composition comprises an emulsion.

3. The composition of any one of claims 1 and 2, wherein the composition comprises an oil-in-water emulsion.

4. The composition of any one of the preceding claims, wherein the gilsonite comprises about 0.01 to about 60 wt. % of the composition.

5. The composition of claim 4, wherein the gilsonite comprises about 0.1 to about 10 wt. % of the composition.

6. The composition of claim 4, wherein the gilsonite comprises about 0.5 to about 5 wt. % of the composition.

7. The composition of any one of the preceding claims, wherein the oil comprises about 1 to about 75 wt. % of the composition.

8. The composition of any one of the preceding claims, wherein the oil comprises about 5 to about 50 wt. % of the composition.

9 The composition of any one of the preceding claims, wherein the oil comprises about 15 to about 30 wt. % of the composition.

10. The composition of any one of the preceding claims, wherein the oil comprises a petroleum-based oil or a bio-based oil.

11. The composition of any one of the preceding claims, wherein the oil comprises a bio-based oil.

12. The composition of claim 11, wherein the bio-based oil comprises vegetable oil.

13. The composition of claim 12, wherein the vegetable oil comprises a soybean oil.

14. The composition of claim 13, wherein the soybean oil is an epoxidized soybean oil.

15. The composition of any one of the preceding claims, wherein the at least one emulsifier is selected from a cationic emulsifier and an anionic emulsifier.

16. The composition of any one of the preceding claims, wherein the at least one emulsifier is selected from a tall oil-based carboxylate and an alkyl amine.

17. A method of rejuvenating an asphalt surface, comprising: identifying an asphalt surface; and applying a composition of any of the preceding claims to the asphalt surface.

18. The composition of any one of claims 1-p, wherein the oil is selected from at least one of an estolide ester or a hydroxylated fatty acid alkyl ester.