Location: Sustainable Biofuels and Co-products Research
Project Number: 8072-41000-110-015-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2024
End Date: Sep 30, 2026
Objective:
In October 2023, the United States Environmental Protection Agency (EPA) announced an impending ban on trichloroethylene (TCE). This solvent is being used to dissolve many organic materials, including asphalt binder. The potential ban is motivated by studies finding the solvent may be linked to various cancers and other health issues such as Parkinson's Disease. However, TCE is still widely used in the asphalt industry for extracting asphalt binder from mineral aggregates in asphalt mixtures. The overall goal of this project is to investigate an alternative solvent(s) which will not be hazardous and will not affect the properties of the recovered asphalt binder.
Approach:
To achieve this objective, the research team will i) identify potential alternative solvents to TCE (biobased, if possible), ii) assess the benefits and drawbacks of each, iii) develop solvent extraction protocol using new solvent, iv) evaluate extracted binder (using identified solvent) for physical properties and compare to TCE extracted and original asphalt binder to study variability and v) introduce an optimum approach to utilize it. The research team will assess current practices within several state Departments of Transportation (DOTs) and around the world through an extensive literature review. The outcome will be identified alternative solvents. An experimental program will be developed and conducted to define the benefits and drawbacks of each solvent alternative. This will include extracting lab-prepared and plant-produced asphalt mixtures. Extracted binders will be tested against reference ones. If a new extraction apparatus is recommended, a framework for future research and development of non-solvent based extraction and recovery device may be considered.
The proposed work will potentially look for a biobased solvent and the outcome of this work could have potential for use in many biobased products including fast pyrolysis oil and it's high-boiling fraction for potential application as a modifier in asphalt binder.
USDA-ARS PI will leverage his expertise to identify suitable biobased solvent, if possible.