UTC 2022 Funding - Cycle 1 Research Projects

Project No.: CY1-LTU-OU-LSU-01
Title: Replacing Fossil Fuel-Based Asphalt Binder with Sustainable Lignin Binder from Wastes
Performing Institution: Louisiana Tech University, University of Oklahoma, and Louisiana State University
Principal Investigators: Joan Lynam, Louisiana Tech University; Syed Ashik Ali, University of Oklahoma; Mostafa Elseifi, Louisiana State University; Nazimuddin Wasiuddin, Louisiana Tech University; Kenneth Hobson, University of Oklahoma.
Start and Anticipated Completion Dates: 10/1/2023-9/30/2024
Abstract: With an increased focus on renewable energy nationally, the availability of fossil fuel-based asphalt binders will continue to become an issue. Consequently, the costs of such asphalt materials are expected to increase significantly in the future. Also, fossil fuel-based binders are not sustainable and are detrimental to the environment. In this study, the multi-institutional research team will use an agricultural waste-based binder to partially replace fossil fuel-based binders. The PIs have recently found that a 6% replacement of fossil fuel-derived binder with a sustainably sourced binder can improve the high temperature performance grade, long-term aging index, and resistance to rutting and cracking performance. In that study, lignin from local Louisiana sources, specifically lignin from a paper mill, sugar cane bagasse, and rice husks (hulls), was used to replace up to 6% of fossil fuel-based binders. However, that study did not include UV oxidation, low-temperature flexibility, and moisture sensitivity that are important to pavement performance. The goal of the present study is to evaluate the effectiveness of using lignin from different sources to replace up to 35% fossil fuel-based binders. The results will demonstrate its effectiveness as a sustainable and renewable paving material. Also, the performance of asphalt mixes with lignin-based binder and Reclaimed Asphalt Pavement (RAP) will be investigated using a balanced mix design (BMD) approach. The proposed research will consist of six tasks divided among the three partner institutions. Task 1 (Louisiana Tech University (LTU) lead) will examine the production of lignin from local waste sources for replacement of traditional fossil fuel-based asphalt binder. Task 2 (LTU lead) will involve incorporation of the derived lignin into binder blends at levels ranging from 8% to 35%. Task 3 (LTU lead) will involve the evaluation of the rheological and chemical properties of binder blends. Task 4 (University of Oklahoma (OU) and Louisiana State University (LSU) co-lead) will consist of collection of aggregates and preparation of control mixes. Task 5 (OU lead) will include an evaluation of the performance of asphalt mixes prepared with lignin binder blend and RAP relative to rutting, cracking, and moisture-induced damage. Task 6 (LSU lead) will include advanced laboratory characterization of asphalt mixes prepared with the lignin-binder blend relative to cracking and moisture susceptibility. The expected outputs include the following: specifications for asphalt binders containing lignin, a balanced mix design protocol for mixes containing RAP and lignin-binder blend, and the effectiveness of lignin from industrial wastes to replace fossil fuel-based binders. Specifically, this study will demonstrate the maximum amount of lignin that can be used to replace the fossil fuel-based binders without compromising performance. These outputs are related to the USDOT’s strategic goal of Climate and Sustainability. The use of lignin as a construction material enhances sustainability and makes the maintenance and rehabilitation of asphalt pavements more environmentally friendly.
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