• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 추계학술발표회요약집
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• pp.296-296
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• 1998

• Carbon letters
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• 제10권4호
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• pp.305-313
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• 2009

In this study, the adsorption of toxic pollutants onto cetyltrimethylammonium kaolin (CTAB-Kaolin) is investigated. The organo-kaolin is synthesized by exchanging cetyltrimethylammonium cations (CTAB) with inorganic ions on the surface of kaolin. The chemical analysis, the structural and textural properties of kaolin and CTAB-kaolin were investigated using elemental analysis, FTIR, SEM and adsorption of nitrogen at $-196^{\circ}C$. The kinetic adsorption and adsorption capacity of the organo-kaolin towards o-xylene, phenol and Cu(II) ion from aqueous solution was investigated. The kinetic adsorption data of o-xylene, phenol and Cu(II) are in agreement with a second order model. The equilibrium adsorption data were found to fit Langmuir equation. The uptake of o-xylene and phenol from their aqueous solution by kaolin, CTAB-kaolin and activated carbon proceed via physisorption. The removal of Cu(II) ion from water depends on the surface properties of the adsorbent. Onto kaolin, the Cu(II) ions are adsorbed through cation exchange with $Na^+$. For CTAB-kaolin, Cu(II) ions are mainly adsorbed via electrostatic attraction with the counter ions in the electric double layer ($Br^-$), via ion pairing, Cu(II) ions removal by the activated carbon is probably related to the carbon-oxygen groups particularly those of acid type. The adsorption capacities of CTAB-kaolin for the investigated adsorbates are considerably higher compared with those of unmodified kaolin. However, the adsorption capacities of the activated carbons are by far higher than those determined for CTAB-kaolin.

• 한국물환경학회지
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• 제28권5호
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• pp.723-728
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• 2012

In this study, zeolites were synthesized by a fusion and a hydrothermal methods using a coal fly ash and a waste catalyst. The recovery performance of metal ions on the structure property of synthetic zeolites was evaluated as comparing the adsorption kinetics (Lagergen 2nd order model) and isotherm (Langmuir model) of $Co^{2+},\;Ni^{2+}$, and $Cu^{2+}$ ions. The synthetic zeolites (Z-C1 and Z-W5) were similarly assigned to XRD peaks in a reagent grade Na-A zeolite (Z-WK : $Na_{12}Al_{12}Si_{12}O_{48}\;27.4H_2O$). Adsorption rates of Z-W5 and Z-C1 were in the order of $Cu^{2+}\;>\;Co^{2+}\;>\;Ni^{2+}\;and\;Ni^{2+}\;>\;Cu^{2+}\;>\;Co^{2+}$, respectively. They had influenced upon structure properties of zeolite. Selectivities of metal ions and maximum equilibrium adsorption capacities, $q_{max}$, in Z-C1 and Z-W5 were in the order of $Ni^{2+}$ (127.9 mg/g) > $Cu^{2+}$ (94.7 mg/g) > $Co^{2+}$ (82.6 mg/g) and $Cu^{2+}$ (141.3 mg/g) > $Co^{2+}$ (122.2 mg/g) > $Ni^{2+}$ (87.6 mg/g), respectively. The results show that the synthetic zeolites, Z-C1 and Z-W5, are able to recover metal ions selectively in wastewater.

• Bulletin of the Korean Chemical Society
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• 제29권9호
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• pp.1774-1780
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• 2008

New PVC based polymeric membrane electrodes (PME) and coated glassy carbon electrodes (CGCE) based on synthesized Schiff base complexes of Co(III); [Co(Salen)$(PBu_3)_2$]$ClO_4$, [Co($Me_2$Salen)$(PBu_3)_2$]$ClO_4$, [Co(Salen)$(PBu_3)H_2O$]$ClO_4$; as anion carriers for potentiometric determination of $ClO_4\;^-$were studied. The PME and also CGCE electrodes prepared with [Co(Me2Salen)$(PBu_3)_2$]$ClO_4$ showed excellent response characteristics to perchlorate ions. The electrodes exhibited Nernstian responses to $ClO_4\;^-$ ions over a wide concentration range with low detection limits ($1.0 {\times} 10^{-6}\;mol\;L^{-1}$ for PME and $9.0 {\times} 10^{-7}\;mol\;L^{-1}$ for CGCE). The electrodes possess fast response time, satisfactory reproducibility, appropriate lifetime and, most importantly, good selectivity toward $ClO_4\;^-$ relative to a variety of other common inorganic anions. The potentiometric response of the electrodes is independent of the pH in the pH range 2.5-8.5. The proposed sensors were used in potentiometric determination of perchlorate ions in mineral water and urine samples. The interaction of the ionophore with perchlorate ions was shown by UV/Vis spectroscopy.

• Journal of Plant Biology
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• 제12권3호
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• pp.1-7
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• 1969

The lethal actions in Arabidopsis thaliana and Lemna polyrhiza brought about by certain inorganic form of Mn, Ba, Hg, Cu salts, and organic form of Na salts, were studied with aseptic artificial media. These metal ions at certain concentrations caused lethality of either Arabidopsis or Lemna when the media were without Ca ion. On the contrary, addition of Ca to the media protected the organisms from such lethality. It was postulated for the present from the proceeding evidence that Ca adsorbed and distributed along the sites between the plasma and cell membrane acts for suppressing permeation of toxic level of metal ions causing the lethality of these plants.

• 한국환경보건학회지
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• 제30권2호
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• pp.161-166
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• 2004

The impact of dissolved wastewater constituents on the treatment of synthetic bisphenol A (BPA) solutions was investigated under a variety of reaction conditions. The laccase enzyme from Trametes vesicolor was used for the BPA treatment. The constituents studied included various inorganic salts, organic compounds and heavy metal ions. BPA degradation was inhibited by sulfate, thiosulfate, sulfide, nitrite, and cyanide ions at 25 mg/$\ell$, 100mg/$\ell$, 25 mg/$\ell$ 150 mg/$\ell$, and 2.5 mg/$\ell$, respectively. However, the inhibitive effects of sulfide and sulfite on BPA degradation were diminished by additional aeration to oxidize them. Formaldehyde significantly reduced the rate of BPA degradation at 1.0% among organic compounds studied. Among heavy metal ions tested, Fe(II) substantially suppressed BPA removal at 1 mM. MgCl$_2$ and CaCl$_2$ exhibited great inhibition of BPA degradation at 25mM.

• 한국환경과학회지
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• 제26권5호
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• pp.591-600
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• 2017

This study was carried out to elucidate the chemical compositions of water-soluble inorganic ions in $PM_{10}$ and $PM_{2.5}$ aerosols collected during summer and winter in downtown Jejusi city. The ratios of $NO_3^-$ to the total mass of ionic species in $PM_{10}$ and $PM_{2.5}$ aerosols largely increase in winter compared to summer, while $SO_4^{2-}$ ratios in both aerosols appear to follow the opposite trend. Moreover, concentrations of $Na^+$, $Mg^{2+}$, $Ca^{2+}$ and $Cl^-$ in $PM_{10}$ and $PM_{2.5-10}$ aerosols are higher in winter than in summer. The nitrate concentrations in $PM_{10}$ and $PM_{2.5}$ aerosols increase with an identical increase in excess ammonium during winter, however, nitrate formation during summer is not important owing to ammonium-poor conditions.

• The Korean Journal of Ecology
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• 제26권3호
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• pp.109-114
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• 2003

고층습지식물의 생리생태학적 특성을 규명하기 위하여 경상남도 양산시에 위치한 정족산 무제치늪에 서식하는 14과 22종의 식물을 대상으로 체내 무기양이온(K, Ca, Mg), 중금속이온(Al, Fe, Mn), 질소 및 인 함량의 계절적인 변화를 정량적으로 분석하였다. 무제치의 물은 15∼30 μ S/cm의 전기전도도(EC)와 pH 5.0∼5.6 (토양 4.3∼5.1)의 산도를 나타내었으며, Ca, Mg과 같은 2가 양이온의 함량이 낮은 반면 높은 중금속함량(특히 Al)을 보여 전형적인 산성토양의 특성을 보였다. 조사된 습지식물은 무기양이온함량에 있어 종간 뚜렷한 차이를 보였으며, 골풀, 진퍼리새, 기장대풀, 억새, 진달래, 산철쭉, 개미탑, 끈끈이주걱은 400 μ Mg DW 이하의 매우 낮은 함량을 나타내었으며, 동의나물, 숫잔대, 산제비난, 멱쇠채, 제비꽃, 바디나물은 체내 높은 무기양이 온 함량을 보였다. 특히 국화과의 멱쇠채와 제비꽃과의 제비꽃은 Ca과 Mg을 축적하는 경향성을 보였으며, 생육이 진전됨에 따라 오이풀과 꽃창포의 무기양이온 함량은 점차 감소하는 양상을 나타내었다. 한편 조사된 대부분의 식물들은 토양의 높은 중금속 함량에도 불구하고 체내 낮은 농도의 중금속을 함유하였으며, 축적된 총 중금속함량 및 조성은 식물 종간에 뚜렷한 차이를 보였다. 토양의 낮은 질소 및 인 함량에도 불구하고 조사된 대부분의 식물종들은 생육초기단계에 있어 비교적 높은 질소 및 인 함유하였으며, 생육이 진전됨에 따라 서서히 감소하는 양상을 나타내었다. 결론적으로 무제치늪에 서식하는 식물종들은 생육초기에 무기양이온 및 질소를 축적하고 생육과정에 이를 재이용하고, 중금속을 배제하는 기작을 발달시킴으로서 빈영양의 산성 환경을 극복하는 것으로 생각된다.

• 분석과학
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• 제37권5호
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• pp.295-305
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• 2024

5-Hydroxymethyl-2-furaldehyde (5-HMF) is considered one of the main quality indexes of various food products. Its metabolism in humans can potentially lead to carcinogenic compounds. Metallic ions such as Zn, Mg, Mn, and Fe have been reported to enhance 5-HMF formation. Recently, studies on adsorbents that can extract specific organic and inorganic substances with one adsorbent have been conducted. However, simultaneous analysis of organic and inorganic materials typically requires distinct pre-treatment and analytical methods, which increase a lot of labor and cost. In this study, hybrid imprinted polymer (HIP) by mixing 5-HMF imprinted polymer (FIP) and zinc ion imprinted polymer (ZIIP) were generated to extract two analytes, Zn ion and 5-HMF, simultaneously. Physicochemical characterization of HIP was conducted by Fourier-transform infrared spectroscopy, scanning electron microscopy, and sorption tests. Extraction conditions including adsorbent mixing ratio, adsorbate mixing range, and equilibrium time were optimized. Freundlich adsorption model was as the best-fitting isotherm model to elucidate the adsorption mechanism. Affinity of Zn ion and 5-HMF on HIP was superior to non-HIP. In conclusion, HIP showed reasonable feasibility that could be used as an adsorbent to be used for simultaneous extraction of organic and inorganic compounds present in the sample.

• 공업화학
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• 제16권5호
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• pp.628-634
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• 2005

Zirconia-alumina 고분자 전구체가 유기물-무기물 용액 방법으로 zirconium acetylacetonate (ZA), aluminium nitrate (AN), polyethylene glycol (PEG), 그리고 에탄올을 이용하여 제조되었다. 고분자 전구체의 열적 특성 및 점도를 시차주사열용량분석기(DSC), 열중량분석기(TGA), 그리고 동적유변측정기를 이용하여 측정하였다. 부피 팽창을 동반하는 강렬한 발열반응이 $140^{\circ}C$에서 일어났다. 고분자 전구체의 부피팽창은 금속물질중에 유기물의 분해반응과 금속양이온과 PEG 사이의 반응에 의한 것이다. 이들 분해반응과 금속양이온과 PEG 사이의 반응에 대한 여부를 적외선분광기(FT-IR)와 $^{13}C$ solid-NMR 결과로부터 확인하였다. 고분자 전구체의 온도가 증가함에 따라 N-O, O-H, 그리고 C=C에서의 피이크 강도가 감소하였다. 이 결과는 강렬한 발열반응시 금속 물질의 분해반응과 PEG와 금속양이온의 반응이 일어났음을 나타내는 것이다. 다공성 파우더는 $800^{\circ}C$에서 2 h 동안 소결과정을 거쳐 결정성 $ZrO_2-Al_2O_3$ 복합체가 되었다.