Source: NORTH DAKOTA STATE UNIV submitted to NRP
PARTNERSHIP: SUSTAINABLE BIO-BASED HIGH VALUE FIRE RETARDANT ADDITIVE DERIVED FROM AGRICULTURAL BYPRODUCTS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
ACTIVE
Funding Source
Reporting Frequency
Annual
Accession No.
1032427
Grant No.
2024-67021-42491
Cumulative Award Amt.
$800,000.00
Proposal No.
2023-10851
Multistate No.
(N/A)
Project Start Date
Jul 1, 2024
Project End Date
Jun 30, 2028
Grant Year
2024
Program Code
[A1531]- Biorefining and Biomanufacturing
Recipient Organization
NORTH DAKOTA STATE UNIV
1310 BOLLEY DR
FARGO,ND 58105-5750
Performing Department
(N/A)
Non Technical Summary
Fire retardant (FR) additives are critical elements integrated into resins to augment their resistance to ignition, diminish flame spread, and restrict fire propagation. While commercially available fire-retardant additives are indispensable for bolstering fire resistance, they may pose several challenges, including environmental impact, production of toxic smoke, carcinogenicity, and performance trade-offs. Particularly of interest are the PFAS-rich surfactants used in aqueous film forming foams, which are crucial ingredient of many fire-fighting materials.In this proposal, our objective is to synthesize 100% biobased, highly efficient universal FR additives in the form of 'nanogels' from agricultural byproducts. We have identified phosphorous-rich organic acid, phytic acid (from wheat bran), and glycerol (from biodiesel production), as the precursors for these universal FR additives.Our promising preliminary data, derived from support from the USDA-NIFA seed grant, clearly demonstrates a versatile approach to incorporating phytic acid into polymeric coating resins. In this proposal, we aim to conduct an in-depth engineering and optimization study on the pathways for extracting phytic acid in a cost-effective manner from agricultural byproducts (objective 1). We will also conduct comprehensive structure-activity and FR-performance studies to establish the efficiency of nanogels over currently available FR additives (objectives 2-3). Finally, Life-cycle and techno-economic analysis will be conducted to identify the carbon footprint of the nanogels as universal FR additives (objective 4). The hyperbranched polyglycerol also demonstrate excellent surface activity especially when chemically conjugated with phytic acids. Therefore, we anticipate the use of polyglycerol and other hyperbranched derviatives will partially replace or reduce the use of PFAS-based surfactants in AFFF formulations (Objective 5). Collectively, this proposal seeks to advance the field of FR additives by focusing on developing novel or enhanced products and processes that leverage agricultural-derived materials. Additionally, the proposal aims to broaden the utilization of waste and byproducts originating from agricultural and food systems.
Animal Health Component
0%
Research Effort Categories
Basic
100%
Applied
0%
Developmental
0%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
51174102020100%
Goals / Objectives
The tragic incident in Maui, Hawaii, in early August 2023, marked by a series of wildfires leading to evacuations, widespread destruction, and claiming the lives of at least 115 individuals with 385 still unaccounted for, serves as a stark reminder of the persistent threat posed by fire--a fundamental element that has profoundly influenced our civilization. This work aims to determine the synthetic pathway toward developing a high-efficiency, intumescent fire-retardant(FR) additive from wheat bran- an agricultural byproduct of North Dakota and Montana by targeting phytic acid (PA) as the principal FR ingredient in fire-fighting formulations. Currently usedFR-additives are halogen-based, create toxic gases and smoke[4], and in many cases do not produce substantial flame-rate suppression properties. On the other hand, PA is a biocompatible FR additivewith excellent fire-retardationproperties.While our group was successful in developing pathways to utilize PA, the questions that remained unanswered were -[1] How can we economically extract PA on a large scale from agricultural byproducts such as wheat bran? [2] What will be the strategy to produce 100% biobased FR agents with PA? [3] How does molecular diversification of PA additive affect the FR mechanism on steel or wood substrates? [4] What will be the life-cycle and carbon footprint analysis of PA-polymer additives compared to commercial FR products?, and [5] How PA can be used to incorporate in a molecular design of an efficient surfactant system, that either replace or reduce the use of PFAS containing surfactants used in aqueous film forming foams (AFFFs).The central hypothesis of our work is -Hyperbranched polyglycerol (hPG) derivatives, obtainedfrom the crude glycerol generated from the biodiesel industry,can be complexed with bio-derived PA after proper chemical modifications toform nanogels that will have show FR-and surface active properties. As such, the major goals of this project are:[1]: Optimization of PA extraction from wheat bran; [2]: Optimization of phytic acid nanogel preparation. [3] Evaluating the performance of phytic acid-enriched FR-nanogels and establishing the molecular mechanisms promoting fire-retardation by the nanogel-infused coating systems, and [4] Evaluate technoeconomic analysis (TEA) and life cycle assessment (LCA) of PA-hPG from wheat bran, and finally [5] Identifying pathways to reduce and replace PFAS-rich surfactants used in AFFFsby exploring thesurfactant properties of PA-derivatives. Successful completion of the project will provide efficient, low-toxicity FR agents, enhance the value-addition of cereal crop agriculture, and identify chemical pathways to biobased surfactants for AFFF products.
Project Methods
Following methods and strategies will be adopted to conduct the proposed project:Optimization of phytic acid extraction from wheat bran.Wheat bran contains 3-5wt% of antinutrient PA and effective extraction of PA will allow us to utilize PA for fire retardant (FR) additive and remaining wheat bran as nutrient-rich animal meal. However, the extraction process needs to be optimized to ensure effective PA extraction without compromising the nutrient content of the wheat bran. In this objective, PA extraction will be performed on wheat bran; the extracted PA will be used for fire regardant additive (Obj. 2); and characterize both PA and wheat bran to generate experimental data for technochemical and life-cycle analysis (TEAand LCA).Optimization of phytic acid nanogel preparation.Nanogels are defined as cross-linked macromolecules that attain a definite 3-D architecture at nanoscale. Usually, nanogel particles are within the size range of 100-300 nm. In our case, we used PA as crosslinker to connect several hyperbranched polyglycerol (hPG)molecules together. Our rational for the study is based on our preliminary data, where we showed that phytic acid has excellent FR-properties at nanoscale, and when chemically/physically connected within a network of macromolecules, can act as a fire-retardant (FR)-additive in the form of nanogels. As such, in this objective, we aim to establish the relationship between gel particle size, surface charge, and PA-loading on the FR-related efficiency of nanogels, when included in commercial coating resins. Thus, Objective 2 is divided into two tasks. In first sub-task, we will identify how molecular parameters of hPG (such as MW, the presence of spacer molecules, peripheral functional groups) affects PA-loading and govern the nanoscale features of the resulting PA-hPG gels (i.e., particle size, surface charge, colloidal stability). In the following steps, we will optimize the concentration of nanogels and its addition conditions to commercial resins and determine the effect of such inclusion on coatings and FR properties under standard conditions. We will identify three (03) best resin formulations infused with these optimized PA-hPG nanogels to identify their FR-mechanism on different substrates for the next step.Evaluating the performance of phytic acid-enriched FR-nanogels and establishing the molecular mechanism promoting fire-retardation by the nanogel-infused coating systems.The three (03) most promising phytic acid-enriched FR-nanogels compositions identified from previous stepwill be evaluated as coatings for wood composites and as a filler in thermoplastics matrices. Our working hypothesis is that modifying phytic acid will produce cross-linked PA-hPG complexes in the form of intumescent nanoscale polymeric nanogels. The gels will enhance the formation of the carbon layer, reducing the heat release rate, extending the ignition time, and reducing the emission of combustible volatiles during fire for an effective FR system. Because nano-gels reduce the mobility of the molecules and the capture of free radicals, nanogels exhibit better thermostability than the original materials, and their fire retardancy depends on the nano-fillers' geometrical shape and chemical structure. Our approach is to modify the surface of the wood matrix by applying phytic acid-enriched FR-nanogels. The hydrophilic nature of the gel will result in strong electrostatic interactions on the interface, resulting in a durable coating on the surface and absorption into wood. For thermoplastic polymers, polyethylene will be the preferred substrate. The phytic acid-enriched nano will be first freeze-dried and then blended as a powder in the matrix. We justify this approach because these two material classes are extensively used in construction and household commodity goods and are intrinsically vulnerable to fire. The addition of phytic acid-enriched FR-nanogels will engineer the nano interfacial interactions of hydrophilic and hydrophobic polymer matrix materials and help in char formation/barrier coating when exposed to fire. These two extreme materials will provide information regarding the structure-property relationship and discovering the FR mechanisms of these gels.Evaluate technoeconomic analysis (TEA) and life cycle assessment (LCA) of fire-retardant additive production from agricultural byproductsAlthough the PA extraction itself is economically viable, we propose to synthesize fire returdant additive from PA. Therefore, we will perform TEA of the entire process from extraction of PA to synthesis of PA-hPGfire returdant additive. TEA will be performed in Aspen Plus software, where the cost of HTC-activation process will be evaluated. The nth-plant assumptions will be made in the present model applied to determine the total capital investment (TCI). Aspen Plus process model computes thermodynamically rigorous material and energy balances for each unit operation in this conceptual process. The material and energy balance data from Aspen simulation will be used in determining the number and size of capital equipment items. Once equipment costs are determined, direct and indirect overhead cost factors (e.g., installation costs and project contingency) can be applied to determine the fixed capital investment (FCI). The FCI, along with the plant operating expenses can be used in a discounted cash flow rate of return analysis to determine a gate price for biosorbent at a given discount rate. This gate price will be required to obtain a net present value (NPV) of zero for a 10 % internal rate of return (IRR) after taxes. The data obtained from the previous tasks will be applied towards mass and energy balances in order to determine energy outputs, unit operation electrical requirements, and product produced for this project. Energy demands/outputs, electrical demands, and flowrates can then be used to determine investment costs (capital, sizing, etc.) and cash flows. In this task, we will complete the TEA analysis of the fire-retardant additive production from agricultural byproducts and revise and include operating cost, cost for mixing and neutralization utilizing HCl and NaOH. All costs will be expressed on a $/ton basis so that it can easily be compared with existing processes. A sensitivity analysis will be conducted to determine the most sensitive factors on TEA.

Progress 07/01/24 to 06/30/25

Outputs
Target Audience:During this reporting period, our efforts primarily targeted twokey audiences: [1] collaborative groups and research colleagues,and [2] industrial partners actively engaged in the field of fire-retardant (FR) materials. These interactions were facilitated through multiple mechanisms, including regular project meetings, presentations of research findings, collaborative manuscript development, proposal submission, and the dissemination of results through peer-reviewed publications. These efforts have strengthened our partnerships, fostered knowledge exchange, and supported the alignment of academic research with industrial applications in fire-retardant technologies along the goals and objectives of this proposal. Changes/Problems:No significant changes or issues occurred during this period. Although the initial graduate student recruitment process was slow, the delay has since been addressed and resolved. What opportunities for training and professional development has the project provided?The project has successfully provided hands-on training to graduate students in advanced chemical synthesis and characterization of macromolecules, such as hyperbranched polymers, proteins, and polypeptides. This training involved gaining a deep understanding of the chemistry of large polymeric molecules and learning how to design and modify their derivatives, particularly for developingfire-retardant materials. In addition, the student received specialized instruction in advanced molecular and materials characterization techniques, including nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC) equipped with multi-angle light scattering (MALLS) detection.Currently, the trainees arecontinuing to expand their expertise by developing novel materials, including nanogels and nanoparticles synthesized from the polymeric molecules designed during this reporting period. As this work progresses, multiple manuscripts focusing on nanoparticle formation and characterization are expected to be submitted for publication later this year. The project supported the training of graduate and undergraduate students in advanced computational tools (i.e. COSMO-RS and VEGA), laboratory techniques (i.e. TGA, FTIR, ICP-MS, LCMS, and cone calorimeter) and data analysis. One graduate student presented project findings at the AIChE Annual Meeting Guidugli (Laura Fronchetti and Toufiq Reza. "Deep Eutectic Solvents As an Eco-Friendly Flame Retardant for Cotton Fabrics" 2024 AIChE Annual Meeting. AIChE, 2024) How have the results been disseminated to communities of interest?Results have been shared through oral presentations at AIChE Annual Meeting (Laura Fronchetti and Toufiq Reza. "Deep Eutectic Solvents As an Eco-Friendly Flame Retardant for Cotton Fabrics" 2024 AIChE Annual Meeting. AIChE, 2024). A manuscript detailing solvent design and environmental screening has been submitted to a peer-reviewed journal. Another article on phytic acid-based coating for flame retardant applications has been published in the Industrial & Engineering Chemistry Research journal (Guidugli, Laura Fronchetti, et al. "Further Understanding of Phytic Acid-Based Deep Eutectic Solvents as Flame Retardants: COSMO Simulation, Physical Characterization, and Vertical Flame Testing."Industrial & Engineering Chemistry Research63.33 (2024): 14811-14820.) What do you plan to do during the next reporting period to accomplish the goals?From a synthetic standpoint, the upcoming reporting period will focus on the development of fire-retardant nanogels utilizing phytic acid and hyperbranched polyglycerol. These nanogels will be engineered by incorporating phytic acid into the core of the hyperbranched polyglycerol framework through either covalent or non-covalent interactions. The surfactant properties of the resulting nanogels will be systematically evaluated and further enhanced through targeted modifications of the polyglycerol backbone. These properties will also be benchmarked against currently available PFAS-containing surfactants to assess comparative performance. Finally, the nanogels will be integrated into coating and composite systems, and their fire-retardant effectiveness will be assessed using cone calorimetry and limiting oxygen index (LOI) measurements. The upcoming reporting period will focus on a new extraction mechanism for phytic acid and the scaling up for the PA extraction utilizing HDES. Further studies will explore the reusability of the solvents and evaluate long-term environmental impacts using a cradle-to-gate life cycle assessment.

Impacts
What was accomplished under these goals? We have successfully completed and validated the full synthesis of biobased hyperbranched polyglycerol derivatives derived from glycerol. The reaction pathway has been standardized and scaled up. The products have been chemically characterized using proton nuclear magnetic resonance (¹H NMR) spectroscopy and gel permeation chromatography (GPC). Our results indicate that the reaction processes developed during this reporting period yielded hyperbranched derivatives with molecular weights ranging from 350 to 450 kilodaltons (kDa, where 1 kDa = 1,000 g/mol) and exhibited high purity. This achievement represents a critical milestone for the project, as the synthesized polyglycerol derivatives will serve as the foundation for developing fire-retardant nanogels and nanogel-infused coating systems. These nanogels will be created by encapsulating phytic acid within the molecular cavities of the polyglycerol structure. Furthermore, the hyperbranched polymers developed during this period will also serve as a basis for the formulation of PFAS-free surfactants. During this reporting period, the project successfully advances its objectives by completing the experimental phase for the synthesis and screening of hydrophobic deep eutectic solvents (HDES) tailored for flame-retardant applications. A comprehensive environmental health and safety (EHS) assessment was conducted, and COSMO-RS modeling was employed to evaluate solvent-PA interactions. Experimental validation was also performed, showing over 90% removal efficiency for phytic acid in the selected systems. Moreover, a new extraction method utilizing water in batch reactors was initiated. Characterization (CHNS,TGA, and FTIR) has been performed and analyzed. Montana State University team contributed to the development of a comprehensive review paper focused on the fire-retardant properties and mechanisms of phytic acid (PA)-based systems in polymeric and bio-based materials. The task included an in-depth literature review, synthesizing findings across various studies, and authored key sections of the manuscript, including the fire retardancy mechanisms, performance evaluations, and application areas of PA. The manuscript work involved analyzing the synergistic effects of PA with metal ions, nitrogen-based compounds, and nanomaterials, and discussing their impacts on thermal stability, char formation, and flammability reduction. This effort provides valuable insights for advancing environmentally friendly flame-retardant technologies and is aligned with project goal and objectives.

Publications

  • Type: Peer Reviewed Journal Articles Status: Published Year Published: 2024 Citation: Title: Further Understanding of Phytic Acid-Based Deep Eutectic Solvents as Flame Retardants: COSMO Simulation, Physical Characterization, and Vertical Flame Testing