Carcinogenic PFAS (per- and polyfluoroalkyl substances) contaminate the tap water of over 100 million Americans. Also, Europe, Asia and Australia suffer from these hard-to-remove ‘forever chemicals’. New PFAS hot spots are identified daily, exposing nearby populations to serious health risks. Several hundred billion USD are estimated to remove PFAS from our tap water in the US alone. PFAS costs Europe more than €50 billion a year in health problems. Current water treatment solutions are struggling with high operating costs, large volumes of concentrated PFAS waste, and reliability. 

CERAFILTEC now proved with its Active Cake Layer Filtration (ACLF) process through various tests over the past 9 months the effective and low-cost removal of different PFAS chemicals including long-chain PFOS, PFOA, PFHxA, and HFPO-DA (GenX). There are also promising results for short-chain PFAS chemicals, e.g. PFBA and PFBS, which will be published after the pilot completion at a customer site. 

The ACLF process has been established by CERAFILTEC team members over the last decade for the selective removal of dissolved ions. Large plants with over 400,000 m³/d (~100 MGD) total capacity are operating successfully where the ACLF operation has become the go-to solution due to substantial cost savings. The same process also works for the removal of PFAS molecules as well as Dissolved Organic Carbon (DOC), Volatile Organic Compounds (VOC), Trihalomethane (THM), humic acids, pharmaceutical residues, odor, taste, and color. Just the adsorbent changes to Powdered Activated Carbon (PAC).

Activated carbon is already known to be an effective adsorbent for the removal of PFAS chemicals. CERAFILTEC’s ACLF process now optimizes how the adsorbent is utilized: Maximizing specific surface areas and shortening adsorption pathways. This is done through covering the ceramic flat sheet membrane with a very thin and loose coating of PAC. All water must pass through this coating. This process is only possible with ceramic flat sheet membranes. It yields highly effective PFAS removal rates and immense cost savings over Granular Activated Carbon (GAC), Ion Exchange (IX), and Reverse Osmosis (RO) processes.

The highly effective and efficient adsorption capabilities are based on two facts:

• The smaller the particle size, the larger the specific surface area, the better the adsorption capacity – PAC is about 25 times smaller than GAC particles
• The closer the particles (adsorbent) are to each other, the thinner the boundary layer between the particles, the shorter the pathways of the contaminants (adsorbates) to the adsorbent – up to 45 faster and most effective adsorption

Both conditions are perfectly combined in CERAFILTEC’s ACLF process for the first time.