US Patent 11970619 Waste tire-derived asphalt modifier

Asphalt binders are modified using fractional products from waste tire pyrolysis, using an initial step of i) at least partially pyrolyzing, separately from such asphaltic binder, whole rubber articles or size-reduced rubber particles to provide one or more pyrolyzed rubber fractions including a pyrolyzed oil fraction having a selected minimum initial boiling point or flash point, and ii) removing some or all polycyclic aromatic hydrocarbon (PAH) compounds from such pyrolyzed oil fraction to provide a reduced-PAH and preferably translucent pyrolyzed oil fraction that may be combined with an asphaltic binder to provide a modified asphalt composition.