Development of a rubber-modified fractionated bio-oil for use as noncrude petroleum binder in flexible pavements

Abstract

The increasing demand for petroleum-derived products coupled with decreasing world crude reserves has led to substantial increases in asphalt pricing. Society’s additional interest in energy independence and use of renewable sources of energy is also a motivation for developing and using more sustainable materials such as binders derived from noncrude petroleum sources for use in highway applications. Iowa State University has been developing noncrude petroleum binders derived from the production of bio-oil via fast pyrolysis of non-food source biorenewable residues. Currently, research has demonstrated that bioasphalt can be used as a modifier, extender, or even as an antioxidant when added to petroleum asphalt. Previous research illustrated concerns with low-temperature cracking and the ability to produce typical binder grades used in the United States. This work aims to develop a biobinder that can replace 100% of the petroleum derived asphalt used in constructing flexible pavements utilizing bio-oil and crumb rubber. Both ambient and cryogenic crumb rubber were used in the research. The outcomes of the processes and formulations illustrates that noncrude petroleum binders can be developed effectively to replace typical paving grades of asphalt such as a PG 64-22 binder.