2021
Research on Soybean Oil as a Sustainable Recycling Agent
Contributor/Checkoff:
Category:
Industrial
Keywords:
BiobasedBiodegradableIndustrial UsesProcessing co-productsProcessing technology
Parent Project:
This is the first year of this project.
Lead Principal Investigator:
Hamzeh Haghshenas, University of Nebraska at Lincoln
Co-Principal Investigators:
Project Code:
709
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:

The aim of this research study is to evaluate the effect of soybean oil, as a locally available, affordable, sustainable, and
environmentally – friendly recycling agent, on the performance of asphalt pavements containing recycled materials. To
accomplish this, the chemical and physical properties of the soybean oil will be characterized by employing different analyses.
The stability of the soybean oil against oxidation will be increased with various treatments to enhance its performance as the recycling agent for the asphalt pavements. Next, the effect of soybean oil on chemical-rheological properties of different asphalt binders will be studied and finally, the obtained results will...

Unique Keywords:
#industrial use – oil
Information And Results
Project Deliverables

In the first year we will focus on developing treatment methods for increasing oxidative stability of the crude and high oleic soybean oil. The research team will conduct a literature review to summarize the effects of chemical species in recycling agents on asphalt binder and mixture properties and performance. In addition, any possible solutions and modifications reported in the literature will be reviewed. We will evaluate crude soybean oil instead of refined/purified edible soybean oil which results in significant savings in materials cost. Using chemical and physical techniques (see Figure 1), undesirable species in the soybean oil that may negatively affect asphalt binders and asphalt mixtures will be identified. We will also consider and examine high oleic soybean oil as an available option in this phase. Then, possible modifications will be performed for increasing the oxidative stability and improving the performance of soybean oil as recycling agent. Removal of free fatty acids, non-oil materials such as proteins and phospholipids from the crude oil by refining process is important since it increases quality and oxidative stability of the oil. However, bleaching and deodorization may not be needed as they are more important for edible oils. Oxidative stability of soybean oil can be increased by a simple chemical/physical process such as activated carbon adsorption. If the crude oil shows desirable properties after such process based on the chemical analysis, the study will continue and rely on this oil. If not, the crude oil will be subjected to refining process that includes degumming and/or alkali treatment.
Since soybean oil is highly unsaturated oil, it is highly susceptible to lipid oxidation. Inhibition from the oxidation of
unsaturated acids in the soybean oil and increasing their stability to thermal degradation will be achieved by addition of asphalt binder modifiers such as a synthetic antioxidant or antioxidant mixtures such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) in different concentrations. The PI and Co-PIs will update the NSB Technical Advisory Committee (TAC) members on the progress of the proposed tasks on a quarterly basis and a final report will be delivered at the end of this phase. We expect to find a procedure to modify soybean oil to be used as a satisfying recycling agent. The outcomes of this phase will be used as an input for the next phase.

Final Project Results

Updated May 19, 2023:

View uploaded report PDF file

We aim to implement this research by placing and testing the asphalt mixture containing improved soybean oil and recycled materials (e.g., RAP) on a one-mile section of Nebraska road and monitor the performance of this section for a few years. If successful, the outcomes of this research will ultimately provide new use of soybean and create an expanded market for this oil. In addition, Nebraskans may find themselves with an improved economy and more sustainable asphalt roads.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.