• Clean Technology
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• v.15 no.4
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• pp.273-279
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• 2009

$SF_6$, which has a high global warming potential, can be decomposed to sulfur and fluorine compounds through hydrolysis by $H_2O$ or oxidation by $O_2$ over solid acid catalysts. In this study ${\gamma}-Al_2O_3$ was employed as the solid acid catalyst for the abatement of $SF_6$ and its catalytic activity was investigated with respect to the reaction temperature and the space velocity. The catalytic activity for $SF_6$ decomposition by the hydrolysis reached the maximum at and above 973 K with the space velocity of $20,000\;ml/g_{-cat}{\cdot}h$, exhibiting a conversion very close to 100%. When the space velocity was lower than $45,000\;ml/g_{-cat}{\cdot}h$, the conversion was maintained at the maximum value. On the other hand, the conversion of $SF_6$ by the oxidation was about 20% under the same conditions. The SEM and XRD analyses revealed that the ${\gamma}-Al_2O_3$ was transformed to ${\alpha}-Al_2O_3$ during the hydrolysis and to $AlF_3$ during the oxidation, respectively. The size of $AlF_3$ after the oxidation was over $20\;{\mu}m$, and its catalytic activity was low due to the low surface area. Therefore, it was concluded that the hydrolysis over ${\gamma}-Al_2O_3$ was much more favorable than the oxidation for the catalytic decomposition of $SF_6$.

• Analytical Science and Technology
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• v.14 no.1
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• pp.72-79
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• 2001

Oxidative decomposition of 2, 4, 6-trichlorophenol(TCP) was studied in aqueous solution. Iron and manganese protoporphyrin [or tetrakis(p-carboxyphenylporphyrin)] and their polymer supported derivatives were used as catalysts, and $KHSO_5$ and tert-butyldroperoxide(TBHP) as oxidants. Metalloporphyrin itself shows very poor catalytic activity in oxidative decomposition of TCP with oxidant. However, very high catalytic activity was observed when metalloporphyrin was chemically bound to newly synthesized polymers or XAD2 resin. Additionally, it revealed much higher catalytic activity in the presence of water-soluble polymers having a electron-donating axial ligand such as pyridine and immidazole. Maleic acid and chloromaleic acid were found in the resulting solution by ESI-MS. Especially, XAD2-supported metalloporphyrins can be reused as catalysts due to insolubility to solvent, and stability against oxidant.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.133-141
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• 2017

This article described the development of transparent antimicrobial oxo-biodegradable (AOB) film with the function of enhanced freshness of food by employing oxo-biodegradable masterbatch (MB) and antimicrobial MB together with organic metal salt, organic acid, or unsaturated fatty acid. Antibacterial test of the AOB film with the different contents of the antimicrobial MB resulted in the significant freshness extension of plum. Tensile strength and elongation rate of the AOB films before UV treatment were similar to those of polyethylene films used as control. The reduced mechanical properties of AOB film after UV treatment (340 nm) suggested that the AOB film could be degraded by oxo biodegradation. The developed AOB films can effectively prevent decomposition of food by providing antibacterial function and preserving freshness.

• 대한방사선방어학회:학술대회논문집
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• 2011.04a
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• pp.166-167
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• 2011

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.272-275
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• 2005

본 실험은 염소계유해유기화합물을 처리하는 목적으로 종래의 초임계수산화법의 결점을 완전히 해결하기 위해서 도달한 것이 질산나트륨을 산화제로서 사용하는 개량된 초임계수 산화법(다단계산화법)이다. 이와 같이 본 연구팀이 개발한 개량된산화법(다단계산화법)은 매우 간단하며 저렴한 염소계유기물 분해처리시스템을 구축하는 것이 가능하다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.350-351
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• 2001

대기환경기준물질 중 하나인 오존은 자외선과 코로나 방전에 의해 대기중에서 생성되며(Heisig et al., 1997), 강력한 산화력을 지니고 있기 때문에 많은 유기화합물, 무기화합물을 산화시킨다. 특히 유기화합물의 올레핀류 뿐만 아니라 방향족핵도 실온에서 빠르게 분해시키는 특징이 있다. 이 산화분해력을 이용하여 오존은 탈색, 탈취 표백 또는 유기화합물의 구조를 결정, 화학제품의 합성 등에 이용되고 있다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.227-230
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• 2001

셀룰로오스는 가장 풍부한 천연 고분자중 하나로 이미 여러 분야에서 사용되어지고 있다. 그러나 최근에 NO$_2$에 의해 부분적으로 산화된 셀룰로오스가 인체에 아무런 독성 없이 흡수되는 것이 알려지게 되면서 의료용으로도 그 이용이 각광받고 있다. 이미 상용화 되어있는 산화셀룰로오스 제품으로는 Johnson ＆ Johnson사의 Interceed와 Surgicel 등이 사용되고 있으며 이들은 이미 FDA에서 의료용으로 승인을 받은 상품들이다. (중략)

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.71-74
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• 1985

In the present study, a tentative mechanism for the decomposition of the hydroperoxide formed during the thermal oxidation of an edible soybean oil was proposed. The soybean oil was thermally oxidized at $120^{\circ}C$ for 7 hrs with air injection at a rate of 120 ml/min. Through kinetic studies of the decomposition process based on the tentative mechanism and the actual experimental data obtained from the hydroperoxide decomposition at 100, 120, 150 and $180^{\circ}C$, it was found that the reaction order of the hydroperoxide decomposition in these conditions was of first order. It was also estimated that the dissociation energy for the hydroperoxide in the same conditions was 15.876 kcal/g. mol.

• Clean Technology
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• v.21 no.1
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• pp.1-11
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• 2015

To address recent environmental pollution, bio plastics such as biodegradable, oxo-biodegradable, and bio-based plastics have attracted much attention in a variety of industrial fields. The critical disadvantages of the weak mechanical strength and expensive product cost were gradually solved by extensive researches. As an alternative for petroleum-based plastics, the bio plastics have been applied to various items. To popularize the bio plastics, certification marks and technical standardization have been developed in the world. This article provide an over view on the recent trend on the commercialization and national certification marks.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.283-283
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• 2015

1,4-dioxane은 페인트, 광택제 및 코팅제의 제조시에 첨가되는 화학물질로 인간에 대한 발암 가능성과 수중에서의 지속성으로 인해 EPA priority pollutant로 지정되어 있다. 이에 최근 고도산화법을 이용한 처리가 계속적으로 연구되고 있으며, UV/$H_2O_2$ 공법을 통하여 수계에서 발견되는 난분해성 유기 오염물의 제거가 효과적인 것으로 밝혀졌다. 하지만 고도산화공정(AOP)은 다량의 에너지 소모와 산화제 투여로 인한 높은 운전비용이 현실적인 적용에 장애가 되고 있다. 한편 상대적으로 저렴한 비용으로 1,4-dioxane을 처리할 수 있다는 장점으로 인하여 생물학적 분해에 대한 많은 연구가 진행되어 왔다. 하지만, 1,4-dioxane에 대한 많은 연구들이 주로 분해미생물의 분리동정 및 회분식 분해특성에 대한 연구들 위주로 보다 실질적인 연속적 처리반응조의 운전결과들은 거의보고 되지 않고 있다. 본 연구는 Lab scale 연속처리반응조의 장기운전 후 pilot plant 현장적용에 앞서 인공폐수와 합성폐수에서의 분해효율 비교 회분식 실험을 통해 합성폐수내 생물학적 분해에 영향을 미치는 inhibitor의 영향을 확인하였으며, 미생물의 배양 조건에 따른 분해효율 비교 회분식 실험과 modeling을 통하여 현장운영 효율을 예측하였다. 이를 반영하여 추후 진행예정인 pilot plant의 현장 적용성 검토 및 최적 설계인자 도출, 장기운전에서의 효율성 증대를 목적으로 한다.