Seunghun Hyun
고려대학교 환경생태공학부 · 환경과학
Seunghun Hyun 교수의 연구실은 주로 변수 전하를 띠는 토양에서 유기산 및 농약의 이동성과 흡착 거동을 규명하는 데 초점을 맞추고 있습니다. 특히 pH, 이온 강도, 금속 이온(예: Ca²⁺) 및 토양 광물의 표면 특성 등이 유기물의 흡착에 미치는 영향을 실험적으로 분석하며, 환경 안정성과 농약 관리 전략 수립을 위한 예측 모델 개발에도 기여하고 있습니다. 연구는 주로 토양의 표면 반응성과 화학적 특성 간의 상관관계를 기반으로 하여, 열대·아열대 지역의 기후적 특성에 적합한 환경 모델링을 목표로 합니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Previous research with phenolic, carboxylic, and urea type organic acids demonstrated that hydrophilic sorption was primarily due to anion exchange, which was linearly correlated to chemical acidity (pKa) and the soil anion exchange capacity. However, for dichlorophenoxyacetic acid (2,4-D), sorption by a kaolinitic soil was much higher than expected relative to all other organic acid-soil data. The enhanced sorption was hypothesized to involve calcium bridging of 2,4-D to hydrophilic domains. In
Sorption of organic acids by variable-charge soil occurs through both hydrophilic and hydrophobic sorption. In this study, the effect of chemical acidity and the type of acidic functional group on the relative contribution of hydrophilic and hydrophobic processes to sorption by a gibbsite-dominated and a kaolinite-dominated variable-charge soils was quantified by measuring sorption isotherms from different electrolytes (CaCl2, Ca(H2PO4)2, and KCl). The A1 soil is dominated by gibbsite whereas th
Sorption data and subsequent predictive models for evaluating acidic pesticide behavior on variable-charge soils are needed to improve pesticide management and environmental stewardship. Previous work demonstrated that sorption of pentachlorophenol (PCP), a model organic acid, was adequately modeled by accounting for pH-and pKa-dependent chemical speciation and using two organic carbon-normalized sorption coefficients; one each for the neutral and anionic species. Such models do not account for
Leachate derived from unlined coal ash disposal facilities is one of the most significant anthropogenic sources of selenium to the environment. To establish a practical framework for predicting transport of selenium in ash leachate, sorption of Se(IV) and Se(VI) from 1 m M CaSO 4 was measured for 18 soils obtained down‐gradient from three ash landfill sites and evaluated with respect to several soil properties. Furthermore, soil attenuation from lab‐generated ash leachate and the effect of Ca 2+
Prosulfuron [1-(4-methoxy-6-methyltriazin-2-yl)-3-[2-(3,3,3-trifluoropropyl) phenylsulfonyl]-urea), a relatively new sulfonylurea herbicide, is a weak acid (pK(a) 3.76), and therefore, will undergo pH-dependent speciation and sorption. Understanding prosulfuron sorption in soils is important for predicting its environmental fate. Soil and solution factors controlling sorption were investigated by measuring prosulfuron sorption on five model sorbents (amorphous silica, alpha-alumina, CaSWy1 montm
Sorption data and subsequent predictive models for evaluating acidic pesticide behavior on variable-charge soils are needed to improve pesticide management and environmental stewardship. Previous work demonstrated that sorption of pentachlorophenol (PCP), a model organic acid, was adequately modeled by accounting for pH- and pKa–dependent chemical speciation and using two organic carbon–normalized sorption coefficients; one each for the neutral and anionic species. Such models do not account for
