A team from Argonne National Laboratory has developed innovative resin-wafer electrodeionization (RW-EDI) technology that is an advanced application of electrodialysis (ED).

With ED, a solution is passed through a channel between ion exchange membranes. An applied electric field causes charged species to cross the membrane, while the neutral species pass down the channel. In RW-EDI, Argonne adds a manufactured wafer that adds conductivity to the process channel, enabling charged species to be recovered at much more dilute levels. RW-EDI uses less electricity than ED and works at much lower concentrations. Th e team is using it for both the recovery of charged products (renewable chemicals) and the removal of charged species from solution (desalination of water).

Argonne’s resin-wafer technology is made from commercially available materials. By controlling dimensions, composition, porosity and conductivity, the resin-wafer technology can be easily adapted to a target product. Nalco Company licensed the RW-EDI technology from Argonne, and Archer Daniels Midland (ADM) will be one of its first end-users. Argonne, Nalco, and ADM are jointly developing the technology to improve energy efficiency and environmental performance in integrated biorefineries. RW-EDI will significantly reduce the cost of producing clean energy, renewable chemicals, and water used in industry.

By controlling dimensions, composition, porosity and conductivity, the resin-wafer technology can be easily adapted to a target product.

One notable use for the technology is to process biomass-based feedstocks into biofuels and chemicals. Specifically, Argonne’s patented technology allows for the deionizing or continuous removal of charged products, like organic acids, from aqueous streams and eliminates the requirement to continuously add neutralizing agents.

Conventional bioprocessing technologies require significant capital expenditures or energy-intensive steps to recover these products, and they typically generate large waste streams. Controlling the processing costs is critical to the commercial success and growth of these product markets, especially if they are to be cost-competitive with fossil-based products.