Cation−π Interactions Contribute to Hydrophobic Humic Acid Removal for the Control of Hydraulically Irreversible Membrane Fouling

• DOI: 10.1021/acs.est.2c07593
• Publication Date: 2023-02-24T15:47:21Z
• Authors: Sohee Park; Seungju Choi; Yeong Kyu Lee; Yongseok Jho; Seoktae Kang; Dong Soo Hwang
• Keywords: Hydrophobic effect; Membrane Fouling; Moiety; Hydrophobe

Hydraulically irreversible membrane fouling is a major problem encountered during membrane-based water purification. Membrane foulants present large hydrophobic fractions, with humic acid (HA) being prevalent example of natural organic matter. Furthermore, HA contains numerous aromatic rings (π electrons), and its interactions are cause fouling. To address this issue, in study, we used the cation−π interaction, which strong noncovalent, competitive interaction water. Because strength depends on combination cations π molecules, utilizing appropriate will effectively remove caused by HA. We performed macroscale experiments to determine cleaning potential test cations, nanomechanically analyzed changes cohesion using surface force apparatus an atomic microscope, molecular dynamics simulations elucidate removal mechanism studied cations. found that addition 1-ethyl-3-methylimidazolium, imidazolium cation moiety, removed layer weakening cohesion, size, hydrophobicity, polarity synergistically affected based interactions.