Document EqRKXjJ93GMvq8xxMgbBQBn8R

NafionTM Circularity Case Study X NafionTM Ion Exchange Materials C Chemours Introduction Chemours' commitment to circularity is evident in our efforts to develop sustainable solutions, promote reduction, reuse and recycling, plus collaborate with customers and stakeholders. By prioritizing circularity, Chemours is working towards a more sustainable future in which resources are managed efficiently, waste is minimized, and environmental impacts are reduced. Chemours is actively working to integrate circular principles into its business models and product designs, with a holistic view of the lifecycle. We emphasize the importance of reducing the environmental footprints of our operations and those of our customers by implementing innovative solutions that promote reduction, recycling, reuse, and repurposing of materials. Chemours also is engaging in collaborations and partnerships to drive circularity across industries. By working together with customers, suppliers, and other stakeholders, we aim to develop comprehensive solutions that promote resource efficiency and waste reduction. Circularity in Ion Exchange With the aim of reducing reliance on virgin materials and contributing to the circular economy, the Chemours NafionTM Technology Team has undertaken a feasibility study. The purpose was to determine whether it was possible to isolate, recover, purify, and recycle NafionTM polymers from used chlor-alkali (CA) membranes. The performance and durability of NafionTM ion exchange membranes make them the products of choice for chlor-alkali electrolysis. They offer leading-edge solutions for energy storage, fuel cells, water electrolysis, ultra-high purity chemical production, and other specialty applications. 2 Applications in which ion exchange membranes are used include: Energy Production Fuel cells to convert hydrogen to electricity Hydrogen Production Water electrolyzers to convert water to hydrogen and oxygen Water Purification Desalination by electrodialysis Advanced Electronics Manufacturing To make and maintain ultrahigh purity specialty chemicals needed for modern day fabrication of integrated circuits Energy Storage Storing energy in flow batteries to stabilize the energy grid and increase renewable energy utilization Chemical Production Manufacturing chemicals using electricity to increase energy efficiency and decrease by-products. For example, the chlor-alkali process that makes chlorine Testing the Recycling Process As the world at large moves towards electrification and decarbonization, the growth rate of many of the applications mentioned in this paper is outpacing membrane supply capacity, making post-industrial recycling a key priority for Chemours. NafionTM ion exchange membranes are designed to excel across a wide range of operating conditions, contributing to fewer process interruptions and less downtime, offering consistent production and reduced energy consumption. However, over time, performance can decline due to impurity accumulation in the membrane. These impurities might include compounds such as iron, calcium, and strontium. The objective of the Chemours NafionTM recycling study was to determine the technical feasibility of extracting impurities and reprocessing the membrane to obtain a recycled film, the properties of which could then be evaluated. The study involved the collection of post-industrial chlor-alkali (CA) membranes N2030 and N2050 from customers. The polymer from the used CA membranes exhibited high levels of impurities such as iron (over 30,000 ppm) and sodium (13,000 ppm). Other contaminants at lower levels were also present. In the purified NafionTM, these contaminants were significantly less -- 37 ppm and 22 ppm, respectively. See Figure 1. 3 (PPM) (PPM) 30000 32100 25000 20000 15000 10000 13000 5000 0 2820 470 321 208 Used NafionTM Polymer Figure 1. 165 Fe 100 50 37 22 12 0 62 44 Na Zr Ca Sr <1 Ba Purified NafionTM Recycled NafionTM Disp. Purified NafionTM Polymer Recycled NafionTM Dispersion Contrary to previous beliefs, the investigation demonstrated that the removal of contaminants from other membrane components can be achieved. Furthermore, the study showed high purity levels, with less than 1 ppm of each contaminant in 100% recycled CA post-industrial NafionTM dispersion (see Table 1). This is a particularly impressive result when compared with the purity and performance specifications for standard NafionTM dispersion. Moreover, Table 2 highlights no appreciable difference in acid capacity between films made from unused polymer and films made from reclaimed CA polymer. Iron (ppm) Chromium (ppm) Nickel (ppm) Potassium (ppm) Table 1. Standard NafionTM Dispersion Specifications < 50 < 50 < 50 < 100 100% Recycled Chlor-alkali NafionTM Dispersion < 1 < 1 < 1 < 1 4 Table 2. Product Total Acid Capacity (meq/g) Standard NafionTM Cast Film 0.95 - 1.10 100% Recycled CA PreIndustrial NafionTM Cast Film 1.05 0.02 100% Recycled CA PostIndustrial NafionTM Cast Film 1.03 0.01 The NafionTM Research and Development Team continues to explore techniques to enable the recycling of NafionTM ionomers from used membranes and various applications. The Next Steps Towards Circularity The potential, as identified in this study, to isolate, recover, purify, and recycle NafionTM membranes is an exciting step in Chemours' development of innovative, high-performance products that address the sustainability needs of our customers. Polymers, in general, take a very long time to break down in the environment. NafionTM polymers present a unique opportunity to recover the polymer itself due to its high chemical durability. The Chemours NafionTM Technology Team has the knowledge and expertise to help enable these industries on their transformative journey towards a safer, cleaner world. This journey encompasses closing the circularity loop by utilizing fewer resources, prolonging the use of existing products and materials, generating less waste and actively promoting polymer reuse and recycling. 1 https://www.theworldcounts.com/challenges/planet-earth/state-of-the-planet/overuse-of-resources-on-earth 2 https://circulareconomy.europa.eu/platform/sites/default/files/1._report_cgr_global_2022.pdf 2023 The Chemours Company FC, LLC. NafionTM and any associated logos are trademarks or copyrights of The Chemours Company FC, LLC. ChemoursTM and the Chemours Logo are trademarks of The Chemours Company. 5