Publications by authors named "Sunho Yoon"

Article Synopsis
  • Upcycling solid waste into advanced adsorbents is explored as a sustainable method for wastewater treatment using aluminum-based metal-organic frameworks (MOFs) synthesized from red mud.
  • The study showcases the development of three different MOFs (MIL-53(Al), MIL-96(Al), and MIL-100(Al)) by optimizing synthesis conditions and organic linkers, leading to effective removal of perfluorooctanoic acid (PFOA) from water.
  • MIL-100(Al) showed the highest adsorption capacity for PFOA due to its large surface area and effective interaction mechanisms, including ion exchange and Lewis acid-base interactions.
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Article Synopsis
  • The presence of specific iron phases in red mud significantly boosted PMS activation, leading to complete degradation of AO7 and potentially enhancing the breakdown of other organic contaminants as well.
  • The study emphasizes the role of sensitized dyes in facilitating interactions between PMS and iron compounds, offering valuable insights for improved environmental remediation strategies.
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Herein, we report the significant effects of natural organic matter contained in natural zeolite (Z-NOM) on the physicochemical characteristics of a Ni/Fe@natural zeolite (NF@NZ) catalyst and its decontamination performance toward the dechlorination of trichloroethylene (TCE). Z-NOM predominantly consists of humic-like substances and has demonstrable utility in the synthesis of bimetallic catalysts. Compared to NF@NZ (devoid of Z-NOM), NF@NZ had increased dispersibility and mobility and showed significant enhancement in the catalytic dechlorination of TCE owing to the encapsulation of Ni/Fe nanoparticles by Z-NOM.

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In this study, a dye pollutant (methyl orange, MO) was effectively oxidized in a hydroxylamine (HA)-assisted Fenton system using various Al/Si/Fe- and Fe-containing minerals. The fastest degradation kinetics of MO were observed in the olivine-HA Fenton system, whereas other Al/Si/Fe and Fe-rich minerals (magnetite and lepidocrocite) demonstrated much slower degradation kinetics. The degradation rate constants were proportional to dissolved Fe(II) quantities in mineral suspensions (R = 0.

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In this study, novel green nano-zerovalent iron (G-NZVI) is synthesized for the first time using onion peel extract for the prevention of rapid surface oxidation and the enhancement of particle dispersibility with a high reductive capacity. The results from various surface analyses revealed that the spherical shape of G-NZVI was fully covered by the onion peel extract composed of polyphenolic compounds with C[double bond, length as m-dash]C-C[double bond, length as m-dash]C unsaturated carbon, C[double bond, length as m-dash]C, C-O, and O-H bonds, resulting in high mobility during column chromatography. Furthermore, the obtained G-NZVI showed the complete removal of 50 mg L of bromate (BrO ) in 2 min under both aerobic ( = 4.

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Although it has recently been reported that notable amounts of rare earth elements (REEs) are present in the residual coal ash, little is currently known regarding the association of these elements with the coal ash matrix, thereby limiting the potential for extraction of REEs from coal ash. In this study, we analyzed the binding characteristics of REEs within coal ash via sequential extraction and examined REE recovery during a coal ash recycling process. Major components of coal ash were found to be mineral oxides, mainly composed of Si, Fe, Al, and Ca, and residual carbons.

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In this study, a novel peroxymonosulfate (PMS) activation method, which combines a solid waste (i.e., red mud, RM) and a reducing agent (i.

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A systematic study was conducted to investigate the effect of major groundwater ions (i.e., Ca, Na, and HCO) on removal of hexavalent chromium (Cr(VI)) by an Fe(II)-phosphate mineral (i.

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Cesium is a typical radioisotope that has a long half-life and is dangerous and can be emitted in the event of a nuclear accident. Prussian blue (PB), which is known to effectively adsorb cesium, is difficult to separate when it is dissolved in an aqueous system. In this study, PB was immobilized on a filter type support media, cellulose filter (CF), for use as a selective material for cesium adsorption.

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We firstly developed a novel synthesis method of nanoscale zerovalent iron (NZVI) using Fe sources in coal fly ash (CFA) for the oxidative degradation of methyl orange by Fenton reaction. Hydrochloric acid (HCl) and methyl isobutyl ketone (MIBK) were used for Fe dissolution from CFA and selective Fe(III) chelation, respectively. Among varied HCl concentrations, 7 N HCl showed the best performance for the oxidation of aqueous Fe(II) to Fe(III) and efficient chelation of Fe(III) with MIBK.

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Experimental and theoretical studies were conducted to identify the molecular-scale reaction mechanism for Cr(VI) removal by a ferrous phosphate mineral, vivianite. The surface-normalized rate constant for Cr(VI) removal in a vivianite suspension at pH 7 was higher than those obtained for other Fe(II)-containing minerals (i.e.

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