Seoul National University · Environmental Science
Professor Yongju Choi's research lab specializes in environmental remediation and resource recovery, focusing on innovative separation and sorption technologies for persistent organic pollutants and valuable gaseous compounds in water and soil. Key research directions include membrane-based gas recovery (e.g., ammonia and methane) from waste streams, activated carbon applications for sequestering polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in contaminated sediments, and the development of robust, hydrophobic membranes to prevent wetting and enhance mass transfer efficiency. The lab integrates experimental studies with predictive mass transfer modeling to optimize in situ remediation and sustainable resource recovery under real-world conditions.
Figures are computed from collected data and may differ slightly.
Membrane gas extraction technique enables recovery of high-purity ammonia from waste streams through gas-phase mass transfer across hydrophobic membranes. This study demonstrates the potential of ammonia recovery with gas permeable membrane, operated at moderately alkaline feed pH, as a substitute for the current approach of biological nitrogen removal in domestic wastewater treatment process. The measured apparent ammonia mass transfer coefficient in 3-h operation at a feed pH of 9.2 was 0.0713
We report polyethylene (PE)-water partitioning coefficients (K(PE)) for 17 parent-polycyclic aromatic hydrocarbons (PAHs), 22 alkylated-PAHs, 3 perdeuterated parent-PAHs, and 100 polychlorinated biphenyl (PCB) congeners or coeluting congener groups. The K(PE) values for compounds in the same homologue group are within 0.2 log units for alkylated-PAHs but span up to an order of magnitude for PCBs, due to the greater contribution of the position of the substituents (i.e., chlorines for PCBs and al
We present a first comprehensive set of experiments that demonstrate the performance of activated carbon (AC) to reduce the availability of polycyclic aromatic hydrocarbons (PAHs) including alkylated-PAHs in petroleum-impacted sediments. The uptake in polyethylene samplers for total PAHs in a well-mixed sediment slurry was reduced up to 99% and 98% for petroleum-impacted sediments with oil contents of 1% and 2%, respectively, by treatment with 5% AC. The AC showed similar efficiency for parent-P
The effectiveness of activated carbon (AC) treatment to sequester hydrophobic organic contaminants in sediments under stagnant contact was comprehensively studied for the first time. Two years of column experiments were conducted to simulate field conditions with two study sediments contaminated with petroleum and polychlorinated biphenyls, respectively, and variations in AC-sediment contact times, initial AC mixing regimes and distribution, AC particle sizes, and pore-water flow. The benefit of
The validity of a hydrophobic organic contaminant mass transfer model to predict the effectiveness of in situ activated carbon (AC) treatment under stagnant sediment-AC contact is studied for different contaminants and sediments. The modeling results and data from a previous 24-month column experiment of uptake in polyethylene samplers are within a factor of 2 for parent- and alkylated-polycyclic aromatic hydrocarbons in petroleum-impacted sediment and factors of 3-10 for polychlorinated bipheny
Open papers in the app to read, cite, and organize with AI.
