1. A method of forming an asphalt mixture comprising:
mixing a bitumen source with a bio-source material to form a bitumen mixture, wherein the bio-source material includes an
oil, wherein the oil includes recycled cooking oil, recycled vegetable oil, recycled animal fat, or any combination thereof;
adding a liquid catalyst to the bitumen mixture form an asphalt mixture, wherein the liquid catalyst includes a metal salt
wherein the metal includes cobalt, manganese, zirconium, vanadium, iron, calcium, nickel, copper, zinc, osmium, rhodium, rhenium,
hafnium, or any combination thereof, wherein the metal salt further includes the salt of an acid, the acid including naphthenic
acid, octanoic acid, 2-ethylhexanoic acid, ethylenediaminetetraacetic acid (EDTA), ethylene glycol tetraacetic acid (EGTA),
or any combination thereof, wherein the liquid catalyst includes a solvent.