• Resources Recycling
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• v.13 no.2
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• pp.3-8
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• 2004

A basic study on the recovery of heavy metals such as Zn, Ni, Cu and Fe ions from wastewater was carried out with the spent iron oxide catalyst, which was used in the Styrene Monomer(SM) production company. The heavy metals could be recovered more than 98％ with the spent iron oxide catalyst. The alkaline components of the spent catalyst could be precipitated the metal ions of the wastewater as metal hydroxides at the higher pH 10.6 in Ni, pH 8.0 in Cu, pH 6.5 in Fe, pH 8.5 in Zn. But the metal ions are adsorbed physically on the surface of the spent catalyst in the range of the pH of the metal hydroxides and pH 3.0, which is the isoelectric point of the iron oxide catalyst.

• Proceedings of the Korea Crystallographic Association Conference
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• 2003.05a
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• pp.26-26
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• 2003

산업 폐기물로서 전량 매립되고 있는 styrene monomer (SM) 공정에서 발생되는 산화철 폐촉매를 사용하여 NiZn-페라이트를 합성하였고, 그 자기적 특성을 조사하였다. 평균입경 0.5㎛로 미분쇄된 산화철 폐촉매에 NiO 및 ZnO를 혼합하여 900℃에서 하소한후 1230℃에서 5시간 동안 소결하여 스핀넬형 페라이트 소결체를 얻었다. Ni/sub x/Zn/ub 1-x/Fe₂O₄(x=0.36, 0.50, 0.66) 및 (Ni/sub 0.5/Zn/sub 0.5/)/sub 1-y/Fe/sub 2+y/O₄(y=-0.02, 0, 0.02) 조성에 대하여 초투자율을 측정하였다. S-parameter를 측정하여 반사 감쇄량을 계산하였다. Ni/sub 0.5/Zn/sub 0.5/fe₂O₄ 조성의 경우 밀도 5.38 g/㎤ kHz에서의 초투자율이 59인 특성을 얻었다. 산화철 폐촉매를 이용하여 X-band 주파수 영역에서 높은 전자파 흡수능을 갖는 전파흡수체를 제조할 수 있음을 확인하였다. Ni/sub 0.5/Zn/sub 0.5/Fe₂O₄ 조성에 대하여 1100℃에서 하소한 분말을 사용하여 실리콘 고무에 복합시킨 후 전파흡수능을 측정하였다. 폐촉매에는 산화철 이외에 CeO₂가 주된 첨가물로 함유되어 있어서 페라이트의 합성 후에도 2차상으로서 존재하였다. 출발 원료인 산화철 폐촉매에 존재하는 K₂O 및 CeO₂를 제거하기 위하여 산처리와 분산제를 이용한 CeO₂ 분리과정을 행하였다. 정제된 산화철 폐촉매에 NiO 및 ZnO를 혼합하여 900℃에서 하소하여 스핀넬형 페라이트를 합성하고 1325℃에서 5시간 소결하였다. 위와 마찬가지로 Ni/sub x/Zn/sub 1-x/Fe₂O₄(x=0.36, 0.50, 0.66)과 (Ni/sub 0.5/Zn/sub 0.5/)/sub 1-y/Fe/sub 2+y/O₄(y=-0.02, 0, 0.02) 조성에 대하여 자기적 특성을 조사하였다.화된 중성자빔으로 측정하였다 BPC-Si를 구부려 슬랩의 곡률반경을 변화시키면서 단색기-시료-검출기가 평행파 반평행배치일 때 Cu(111), (200), (220), (311), (331), (420)면의 회절선을 측정하여 각 조건에서 분해능과 강도를 평가하였다.료의 가시적 변화를 통해 illumination angle 1.25mrad(Dose rate : 334 × 10³ e/sup -//sec·n㎡)일 경우 약 3초 이내에 비정질화가 시작됨을 알 수 있었고 이는 약 1 × 10/sup 6/ e/sup -//sec·n㎡ 의 전자선량에 해당되며 이를 기준으로 각각의 illumination angle에 대한 임계전자선량을 평가할 수 있었다. 실질적으로 Cibbsite와 같은 무기수화물의 직접가열실험 시 전자빔 조사에 의해 야기되는 상전이 영향을 배제하고 실험을 수행하려면 illumination angle 0.2mrad (Dose rate : 8000 e/sup -//sec·n㎡)이하로 관찰하고 기록되어야 함을 본 자료로부터 알 수 있었다.운동횟수에 의한 영향으로써 운동시간을 1일 6시간으로 설정하여, 운동횟수를 결정하기 위하여 오전, 오후에 각 3시간씩 운동시키는 방법과 오전부터 6시간동안 운동시키는 두 방법을 이용하여 품질을 비교하였다. 각 조건에 따라 운동시킨 참돔의 수분함량을 나타낸 것으로, 2회(오전 3시간, 오후 3시간)에 나누어서 운동시키기 위한 육의 수분함량은 73.37±2.02%를 나타냈으며, 1회(6시간 운동)운동시키기 위한 육은 71.74±1.66%을 나타내었다. 각각의 운동조건에서 양식된 참돔은 사육초기에는 큰 변화가 없었으나, 사육 5일 이후에는 수분함량이 증가하여 15일에는 76.40±0.14, 75.62±0.98%의 수분함량을 2회와 1회 운동시킨 참돔의 육에서 각각 나타났다. 운동횟수에 따른 지질함량은 2회 운동시킨 참돔은 5.83±2.08, 1회 운

• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.402-408
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• 2005

This investigation aimed at selecting the optimum catalyst and reaction conditions used in Fenton oxidation for landfill leachate treatment and was carried out at ambient temperature using a lab-scale experiment. The investigation led to the following results: 1) The optimum pH and dose for each iron catalyst were as follows: $Fe^{2+}\;=\;1,200\;mg/L$, $H_2O_2\;=\;1,200\;mg/L$, initial pH=3.0; $Fe^{3+}\;=\;1,200\;mg/L$, $H_2O_2\;=\;1,500\;mg/L$, initial pH=4.5; $Fe^0\;=\;1,200\;mg/L$, $H_2O_2\;=\;900\;mg/L$, initial pH=4.0, respectively. 2) The progress of Fenton oxidation could be instrumentally monitored by measuring redox potential evolution during leachate oxidation, thus, indicating the possibility of an on-line process monitoring. 3) A simple acid-base titration of Fenton-treated leachate proved that a relevant fraction of by- products formed during the treatment was made of acidic compounds in the optimum reaction condition for each catalyst used, thus demonstrating that the higher the extent of Fenton oxidation the greater was the amount of acids formed. 4) With the aim of selecting the optimum catalyst among $Fe^0$, $Fe^{2+}$ and $Fe^{3+}$, removal efficiency of each parameter in the optimum reaction conditions was considered. Although $Fe^{3+}$ was higher than other catalysts($Fe^0$, $Fe^{2+}$) in removal efficiency, $Fe^0$ was a optimum catalyst with a view of cost effectiveness.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.22 no.3
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• pp.127-134
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• 2016

In this study, Biodegradable masterbatch (M/B) was prepared by different kinds and content of biodegradable catalysts added to oxo biodegradable plastics. The bio film was prepared by adding biodegradable M/B to the polyethylene pellet, and the change of physical properties by UV and heat treatment and the stability as food packaging material were confirmed. As a result of the physical property change, Fe salt and Al salt bio film was superior to Ni salt bio film about a decrease in physical property. However, considering the raw material cost and industrial availability, M/B containing Fe salt was selected and additional experiments were conducted by concentration. The bio films prepared with Fe salt M/B 1.0, 1.5 and 2.0 wt% showed excellent physical properties.

• Journal of the Korean Ceramic Society
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• v.41 no.6
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• pp.485-492
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• 2004

We prepared cylindrical y-alumina pellets using amorphous alumina and pore generating agent. The pellets were immersed in an aqueous solution of the mixture of Fe(NO$_3$)$_3$ㆍ9$H_{2}O$ and $CH_3$COOH. They were then hydrothermally treated at 20$0^{\circ}C$ for 3 h in autoclave, dried and calcined. For the application of environmental catalyst for its, we investigated the decomposition characteristics of 4-chlorophenol and the initiation characteristics of OH' conversion action in $O_3$ environment with or without the Fe$_2$O$_3$ supported ${\gamma}$-alumina catalyst and $O_3$ molecule.

• Journal of Soil and Groundwater Environment
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• v.6 no.3
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• pp.13-20
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• 2001

In this Study, application of ${H_2}{O_2}$/$Fe^0 oxidation System (Fenton-like oxidation) for the oxidative treatment of high-level soil contamination with hydrocarbon was suggested. The characteristics of Fenton-like oxidation of diesel-contaminated fine soil was experimentally probed in a batch system varying initial pH, zero valent iron and hydrogen peroxide levels, and initial diesel concentration. Contaminant degradation was identified by total petroleum hydrocarbon(TPH) concentration with gas chromatography. The batch experiments showed that the optimal ${H_2}{O_2}$and $Fe^0 dosage, 10% ${H_2}{O_2}$+ 20% $Fe^0 removed 65% of initial TPH concentration (10,000mg/kg) at a retention time of 24h. And the TPH removal in the ${H_2}{O_2}$/$Fe^0 system effectively proceeded only within a limited pH range of 3-4. The zero valent iron-catalyzed Fenton-like oxidation of diesel-contaminated soil was more competitive to the $FeSO_4-catalyzed system (Fenton oxidation) in removal efficiency and cost especially for the treatment of high level contamination.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.81-86
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• 2010

On adsorbing carbon monoxide (CO) on the silica supported ruthenium/iron alloy ($Ru/Fe-SiO_2$) samples above mole ratio 9/1 of Ru/Fe five bands ($2138.7{\sim}2142.5cm^{-1}$, $2067.3{\sim}2073.1cm^{-1}$, $1976.7{\sim}2017.2cm^{-1}$, $1737.9{\sim}1799.3cm^{-1}$, $1625.7cm^{-1}$) were observed, and in $Ru/Fe-SiO_2$ samples below mole ratio 8/2 of Ru/Fe two bands ($1934.0{\sim}1990.2cm^{-1}$, $1625.7cm^{-1}$) were observed. The $2138.7{\sim}2142.5cm^{-1}$ bands, the $2067.3{\sim}2073.1cm^{-1}$ bands, and the $1988.3{\sim}2030.7cm^{-1}$ bands may be ascribed to stretching vibrations of CO molecules lineally bonded to the Ru atoms on supported Ru/Fe cluster surface, the $1737.9{\sim}1799.3cm^{-1}$ bands to stretching vibrations of CO molecules bridge bonded to the Ru atoms on supported Ru/Fe cluster surface or to stretching vibrations of CO molecules bonded to the Ru atoms on high Miller index planes, and the $1934.0{\sim}1990.2cm^{-1}$ bands to stretching vibrations of CO molecules lineally bonded to the Fe atoms on supported Ru/Fe cluster surface. The absorbances of the $1934.0{\sim}1990.2cm^{-1}$ bands in $Ru/Fe-SiO_2$ samples gradually increased with the increases of Ru/Fe mole ratio below the ratio of 8/2. This phenomena may be ascribed to the increases of Fe concentration of surface compared with the one of the sample and to the increases of surface area of supported Ru/Fe cluster according as increase of Ru/Fe mole ratio below the ratio of 8/2 compared with the $Fe-SiO_2$ sample.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.328-333
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• 2004

To treat a waste gas containing a high strength H2S, the two-stages microbial desulfurization process that conof a bioreactor immobilized with Acidithiobacillusferrooxidans and a chemical absorption scrubber has was proposed. After 4 times repeat of batch cultures, the immobilized bioreactor has been stabilized and the rate of iron oxidation reached 0.89 kg . $m^{-3}{\cdot}m^{-1}$ at steady state. The two-stages microbial desulfurization prowas able to be operated for a long term over 54 days. The removal efficiencies of H2S were 97-99% at a space velocity of 70 h-I and a inlet concentration of 37,000 ppmv. The maximum elimination capacity of H2S was approximately 3.3 kg S . $m^{-3}{\cdot}m^{-1}$. In the bioractor, the concentrations of the $Fe^{3+}$ and the immobilzed cell were constantly maintained during the desulfurization.

• Analytical Science and Technology
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• v.14 no.4
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• pp.317-323
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• 2001

Dissolution procedures of Monsanto catalyst which has been used to produce acrylronitrile by ammoxidation of propylene have been studied. Optimum dissolution condition of the catalyst supported on silica was obtained by microwave digestion system with mixed of HCl, HF and $H_2O_2$. When a safety device was activated by increased pressure in microwave vessel, Bi, Fe, Mo, Sb and U were not volatilized even though silica was volatilized as $SiF_4$. Quantification results by this method were $SiO_2$ $50.5{\pm}0.4%$, $Sb_2O_3$ $29.6{\pm}0.6%$, $UO_2$ $10.2{\pm}0.1%$, $Fe_2O_3$ $6.1{\pm}0.1%$, $MoO_3$ $0.73{\pm}0.01%$ and $Bi_2O_3$ $0.49{\pm}0.01%$ by ICP-AES and the relative error was within ${\pm}10%$ except bismuth.

• Korean Chemical Engineering Research
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• v.55 no.3
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• pp.436-442
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• 2017

Fischer-Tropsch synthesis is the technology of converting a syngas (CO+$H_2$) derived from such as coal, natural gas and biomass into a hydrocarbon using a catalyst. The catalyst used in the Fischer-Tropsch synthesis consists of active metal, promoter and support. The types of these components and composition affect the reaction activity and product selectivity. In this study, we manufactured an iron catalyst using ${\gamma}-Al_2O_3/SiO_2$ mixed support (100/0 wt%, 75/25 wt%, 50/50 wt%, 25/75 wt%, 0/100 wt%) by an impregnation method to investigate how the composition of ${\gamma}-Al_2O_3/SiO_2$ mixed support effects on the reaction activity and product selectivity. The physical properties of catalyst were analyzed by $N_2$ physical adsorption and X-Ray diffraction method. The Fischer-Tropsch synthesis was conducted at $300^{\circ}C$, 20bar in a fixed bed reactor for 60h. According to the results of the $N_2$ physical adsorption analysis, the BET surface area decreases as the composition of ${\gamma}-Al_2O_3$ decreases, and the pore volume and pore average diameter increase as the composition of ${\gamma}-Al_2O_3$ decreases except for the composition of ${\gamma}-Al_2O_3/SiO_2$ of 50/50 wt%. By the results of the X-Ray diffraction analysis, the particle size of ${\alpha}-Fe_2O_3$ decreases as the composition of ${\gamma}-Al_2O_3$ decreases. As a result of the Fischer-Tropsch synthesis, the CO conversion decreases as the composition of ${\gamma}-Al_2O_3$ decreases, and the selectivity of C1-C4 decreases until the composition of ${\gamma}-Al_2O_3$ was 25 wt%. In contrast, the selectivity of C5+ increases until the composition of ${\gamma}-Al_2O_3$ is 25 wt%.