Asphalt emulsion surface treatment containing sterol
Pavement aging can be reduced by applying to an asphalt-containing pavement a topcoat layer or a surface treatment containing asphalt binder emulsion with sterols.
1. A method of road paving comprising:
providing sterol-containing asphalt binder emulsion, wherein sterol is added to an asphalt binder from 0.5 to 15 wt. % of the sterol based on the asphalt binder before emulsification;
combining the sterol-containing asphalt binder emulsion with aggregate to form an asphalt paving material;
applying the asphalt paving material atop an asphalt pavement layer; and
compacting the applied asphalt paving material to form a road pavement having a sterol-containing topcoat layer.
2. The method of claim 1 , wherein the asphalt pavement material is applied to the topmost layer of the road pavement as a thin lay comprising an average thickness up to about 65 mm.
3. The method of claim 1 , wherein the pavement material is applied to the topmost layer of the road pavement as a thin lay comprising an average thickness up to about 12 mm to about 38 mm.
4. The method of claim 1 , wherein the sterol is 1 to 10 wt. % of the asphalt binder weight.
5. The method of claim 1 , wherein the sterol is 1 to 3 wt. % of the asphalt binder weight.
6. The method of claim 1 , wherein the sterol comprises a pure sterol, a crude sterol, cholesterol, a plant sterol or combinations thereof.
7. The method of claim 6 , wherein the crude sterol is obtained from a bio-derived source or distilled residue of the bio-derived source.
8. The method of claim 6 , wherein the crude sterol comprises a tall oil pitch.
9. The method of claim 6 , wherein the crude sterol comprises crude sterol derived from soybean oil, or wherein the crude sterol comprises crude sterol derived from corn oil.
10. The method of claim 1 , further comprising adding reclaimed asphalt binder from recycled asphalt pavement (RAP), recycled asphalt shingles (RAS), softening agents, or a combination of RAP, RAS, and softening agents.
11. The method of claim 1 , wherein the sterol-containing asphalt binder provides a ΔTc of greater than or equal to −5.0° C.
12. A paved road made from the asphalt paving material method of claim 1 .
13. A paved road made from the asphalt paving material of claim 10 .