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Title |
A Study on Improving PFAS Adsorption Efficiency by Mixing Biomass Based Activated Carbons
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Authors |
최재영(Jaeyoung Choi) ; 김지민(Jimin Kim) ; 류건영(Gunyoung Ryu) ; 오희경(Heekyong Oh) |
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DOI |
https://doi.org/10.15681/KSWE.2026.42.1.36 |
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Keywords |
Activated carbon; Adsorption; Electrostatic repulsion; Hydrophobicity; PFAS; RSSCT |
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Abstract |
Per- and polyfluoroalkyl substances(PFAS) are commonly used across various industries due to their stable structure. However, these characteristics make PFAS challenging to degrade and remove. This study investigated the use of biomass-derived activated carbon(AC) as an alternative to coal-based AC for PFAS removal during water treatment. The adsorption capacities of coal, bamboo, and coconut-based AC were evaluated in relation to their characteristics, including iodine number, zeta-potential, surface area, and pore volume. Coal-based AC demonstrated the highest PFAS adsorption capacity(6.02?6.11 μg/g), regardless of chain length. In contrast, bamboo-based AC had the lowest adsorption capacity(3.53?5.7 μg/g) due to strong negative zeta-potential, which resulted in electrostatic repulsion, particularly for short-chains. Coconut-based AC showed better adsorption than bamboo, but long-chain PFAS caused pore-blocking in the AC micropores, disrupting the adsorption. As Bamboo-based AC is effective at removing long-chains, a mixture of bamboo-coconut AC in a 1:2 ratio can reduce pore-blocking, thereby increasing the adsorption than using alone. A rapid small-scale column test was conducted using the optimal bamboo-coconut AC mixture, applying influent of each PFAS concentrations normally at 10 ng/L, and high concentration at 625 ng/L. During the second high-concentration injection(27.2k BV), PFBA reached its breakthrough point, surpassing the concentration of influent. Initially, short-chains were removed more effectively than long-chains; however, around 15.5k and 34k BV, the removal efficiency of long-chains surpassed that of short chains. The results indicate that the combination of AC types enhances the removal of PFSAs and long-chains, but additional research is necessary to improve the removal of short-chains.
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