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Take Command of Short and Long Chain PFAS in Drinking Water

Purolite's Purofine® PFA694E resin achieves better, more complete removal of short- and long- chain PFAS than bituminous GAC, and commercial treatment data from municipal wells proves it. Purofine PFA694E acts as both an ion exchange resin and an adsorbent resin with exceptionally high kinetics and selectivity for removing PFAS. This means faster, more thorough removal of PFAS to non-detectable levels when compared with coconut shell and bituminous granular activated carbon (GAC) media. And once the contamination is removed—it stays removed—and doesn’t leak back into the system.

Plus, resin treatment systems are better for tax payers and the environment as long-term operating costs and up-front capital expenses are lower and there is much less media to incinerate.

Operating capacity of the resin is generally much higher than for GAC, so less frequent media change-outs are needed—saving operator time and budget dollars. Plus, the faster acting Purofine PFA694E resin requires vessels that are about half the size of GAC vessels, necessitating less media, a much smaller footprint and less overhead space than GAC systems. Additionally, the volume of wastewater is dramatically reduced as Purofine PFA694E is only back washed once at startup—there is no need for large backwash pumps and water storage tanks like there is with GAC systems.

Integrating a resin is not difficult as existing GAC systems can be retrofitted to work with Purofine PFA694E, either alone or as a GAC polisher. Each system and water chemistry is unique, and Purolite will develop the most effective system that makes the most economic sense for your municipality.

Keeping a tight rein on short-and long-chain PFAS (including PFOS, PFOA, PFHxS, PFHpA, PFHxA and PFBS) demonstrates your commitment to removing PFAS from municipal systems and keeping residents safe and healthy. If you wish to evaluate resin for a new PFAS removal system or are considering retrofitting an existing carbon system to include resin, Purolite can readily provide capacity and ROI cost estimates.

Purolite experts were honored to contribute to the Interstate Technologies Regulatory Council (ITRC) manual on PFAS remediation using selective ion exchange: Ion Exchange Resin and to section Single-Use IX featuring a case study at Horsham Township, Pennsylvania.

Advantages of IX vs. GAC for PFAS treatment
When selecting a method to remove PFAS from water supplies, it is best to consider the benefits of all the options. Ion exchange resins outperform GAC with a smaller equipment footprint, treat more bed volumes and remove short-chain contaminants.

Purolite's Solution
Purolite has designed, developed and commercially tested a special ion exchange resin with high selectivity for poly- and perfluoroalkyl substances. Purofine PFA694E resin is a single-use proprietary, uniform particle size resin with the dual removal mechanisms of ion exchange and adsorption technology built into each bead for maximum uptake of PFAS.

Water treated with this resin will consistently achieve simultaneous removal of both short- and long chain PFAS—including PFOA, PFOS, PFNA, PFHxA, PFHxS, PFHpA, PFBS and PFBA— to non-detectable levels.

And because it is a high-capacity, single-use resin, there is no need for regenerant chemicals or methanol that can increase the corrosiveness of treated water. All exhausted resin gets incinerated, which completely breaks down the compounds, preventing re-introduction into the environment.

​Advantages of Purofine PFA694E:

  • Can simultaneously reduce both short and long-chain PFAS to non-detectable (ND) levels (< 1 to 2 ppt depending on lab accuracy)
  • Can achieve > 99.99% reduction for high concentrations (e.g. 770,000 ppt to < ND)
  • Displays at least 5 to 10 times higher PFAS capacity vs.  granular activated carbon (GAC)
  • Is economical for single-use application followed by high-temperature incineration
  • Requires shorter contact times of 1.5 – 5 mins. vs. 12 – 25 mins. for GAC and is ideal for municipal as well as POE and POU applications
  • Capital equipment/installation cost is about ½ that for GAC
  • Operating cost typically lower than GAC (inclusive of cost for extraction/refill/ trucking/profiling and high-temperature incineration)
  • Can be used either for primary removal of PFAS or as polisher to GAC

For convenience, PFAS are divided into two groups – “long chain” and “short-chain” PFAS. Long-chain includes carboxylic types such as PFOA and PFNA with ≥ 8 carbons and sulfonic type PFOS with≥ 6 carbons.