• 한국지반환경공학회 논문집
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• 제12권9호
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• pp.55-61
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• 2011

본 연구는 UV와 $H_2O_2$를 통한 광분해 반응기에서의 Methyl Tert Butyl Ether(MTBE) 제거에 대해 조사하였다. 이 공정은 일반적으로 UV의 존재 하에 수용액 상에 생성되는 OH 라디칼을 요구하며, 이 라디칼들은 MTBE 분자를 공격하여 최종적으로 파괴하거나 무해한 단순 화합물로 전환시킨다. 반응들은 조사강도, MTBE 초기농도와 $H_2O_2$/MTBE비의 독립변수를 수학적으로 표현하였고, 반응표면법(Response Surface Methodology; RSM)을 사용하여 모델화하였다. 이 실험들은 Box-Behnken Design(BBD)를 통한 15개의 실험을 포함하여 실시하였다. ANOVA의 회귀분석 항은 유의한 p-value(p<0.05)와 높은 결정계수($R^2$=94.60%)를 나타내어 2차 회귀모델의 예측이 적절한 것으로 나타났다. 그리고 반응에 대한 정준분석을 통해 예측된 Y에 대한 최적 반응과 최대반응의 예측된 능선을 통해 최적조건은 각각 조사강도인 $x_1$=25.75W, MTBE 초기농도의 $x_2$=7.69mg/L 와 $H_2O_2$/MTBE비인 $x_3$=11.04로 관찰되었다. 본 연구는 RSM이 MTBE 제거의 최대화와 운전조건의 최적화에 적용하기에 알맞은 것으로 나타났다.

• 한국태양에너지학회 논문집
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• 제21권2호
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• pp.55-67
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• 2001

This study contains the photocatalytic degradation of methyl-tert-butyl ether(MTBE), one of water-contaminating substances, into $CO_2$. Herein was investigated factors, kinetics, and reaction pathways related with MTBE degradation. This works is possible to be applied in the field of environmental remediation such as undergroundwater purification with optimized system configuration in the near future.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.31-35
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• 2005

본 연구는 토양에 휘발유 첨가제인 MTBE와 휘발유의 주성분인 BTEX를 headspace 법에 의해 동시 분석하는 방법이다. 인산으로 pH를 2로 조절한 후 NaCl로 포화시킨 용액 5ml를 헤드스페이스 바이알에 보존제로 넣은 후 토양시료 약 2g을 이 용액에 침지시켜 시료 채취한 다음 헤드스페이스 장치에 넣고 $80^{\circ}C$에서 40분 가온하여 상부 기상의 일정량을 취해 GC-MS (SIM)으로 분석하였다. 본 분석법에 의한 검출한계는 methyl-tert-butyl ether(MTBE)와 benzene, toluene, ethylbenzene, o,m,p-xylene(BTEX)이 각각 0.1, 0.1, 0.1, 0.2, 0.1, 0.2 ng/g이었고, 직선성은 0.995이상이었으며, 재현성도 10%내외의 정밀한 값을 보였다. 실제 시료를 분석한 결과, MTBE가 3-6,993 ng/g의 농도분포를 보였고 total BTEX는 1 ng/g으로 검출되었다. 이 방법은 빠르고 정밀 정확한 분석법으로 공정시험법으로 활용가치가 높다.

• International Journal of Automotive Technology
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• 제6권3호
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• pp.197-203
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• 2005

This paper investigates the effect of oxygen composition in mixed fuel on the exhaust emissions for the direct injection diesel engine. These effects were tested to estimate the change in engine performance and exhaust emission characteristics when commercial diesel fuel and oxygenates blended fuels at a certain fuel and mixed ratio are used. Individual hydrocarbons $(C_1-C_6)$ in exhaust gases, as well as the total amount of hydrocarbons, were analyzed by using gas chromatography to find the mechanism by which smoke emission was remarkably reduced for various oxygenated fuels. The chromatograms between a diesel fuel and a diesel fuel blended DGM (diethylene glycol dimethyl ether), MTBE (methyl tert-butyl ether) and EGBE (ethylene glycol mono-n-butyl ether) were compared. The results showed that the number of individual hydrocarbons as well as the total number of hydrocarbons of oxygenated fuel reduced more remarkably than those of diesel fuel.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.207-208
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• 2006

Earthworms have been widely used as bioindicators for soil ecotoxicity assessment. Ecotoxicity of methyl tert-butyl ether(MTBE) to terrestrial organisms were evaluated by- earthworm assay. Test earthworm species were Perionyx excavatus and Eisenia andrei. The. toxicity test was performed based on a OECD guideline No. 207 with slight modification. Mortality and abnormal morphology of earthworms exposed to different concentrations of MTBE were measured. Toxic levels of MTBE were determined by measuring the median lethal concentration (LC5O) after 72 hours. The toxicity data was statistically analyzed by Trimmed Spearman-Harbor method. This study showed that, P. excavatus is more sensitive to E. andrei, and that earthworm assay can be a good protocol to evaluate the soils contaminated gasoline components.

• Korean Chemical Engineering Research
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• 제43권3호
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• pp.387-392
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• 2005

Dimethyl carbonate(DMC)는 낮은 독성과 빠른 생분해성으로 인해 MTBE(methyl tert-butyl ether)를 대체할 수 있는 무연가솔린의 첨가제로 주목받는 물질로, 주로 methanol의 carbonylation에 의해 합성되고, 원가절감을 위해 methanol을 출발물질로 한 새로운 DMC 제조공정의 개발이 진행 중에 있다. 이에 필요한 다양한 조건하의 DMC 관련 혼합계의 상평형 자료 및 물성은 Dortmund Data Bank(DDB)검색 결과, 매우 부족하며 무한희석 활동도계수에 대한 자료는 전무한 것으로 나타났다. 이 글에서는 methanol+DMC계의 333.15 K에서의 이성분계 등온 기-액 평형과, 혼합물성으로써 methanol+DMC계의 과잉부피 및 점도편차를 298.15 K에서 측정하였다. 또한, 무한희석상태에서 DMC 용매에서의 methanol의 무한희석 활동도계수를 303.15, 313.15, 323.15 K에서 각각 측정하였으며, 측정값은 modified UNIFAC(Dortmund)식에 의한 계산 값과도 비교하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권2호
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• pp.15-21
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• 2012

MTBE (Methyl tertiary-butyl ether) has been commonly used as an octane enhancer to replace tetraethyl lead in gasoline, because MTBE increases the efficiency of combustion and decreases the emission of carbon monoxide. However, MTBE has been found in groundwater from the fuel spills and leaks in the UST (Underground Storage Tank). Fenton's oxidation, an advanced oxidation catalyzed with ferrous iron, is successful in removing MTBE in groundwater. However, Fenton's oxidation requires the continuous addition of dissolved $Fe^{2+}$. Zero-valent iron is available as a source of catalytic ferrous iron of MFO (Modified Fenton's Oxidation) and has been studied for use in PRBs (Permeable Reactive Barriers) as a reactive material. Therefore, this study investigated the condition of optimization in MFO-PRBs using waste zero-valent iron (ZVI) with the waste steel scrap to treat MTBE contaminated groundwater. Batch tests were examined to find optimal molar ratio of MTBE : $H_2O_2$ on extent to degradation of MTBE in groundwater at pH 7 with 10% waste ZVI. As the results, the ratio of optimization of MTBE to hydrogen peroxide for MFO was determined to be 1:300[mM]. The column experiment was conducted to know applicability of MFO-PRBs for MTBE remediation in groundwater. As the results of column test, MTBE was removed 87% of the initial concentration during 120days of operational period. Interestingly, MTBE was degraded not only within waste ZVI column but also within sand column. It means the aquifer may affect continuously the MTBE contaminated groundwater after throughout the waste ZVI barrier. The residual products showed acetone, TBF (Tert-butyl formate) and TBA (Tert-butyl acetate) during this test. The results of the present study showed that the recycled materials can be effectively used for not only a source of catalytic ferrous iron but also a reactive material of the MFO-PRBs to remove MTBE in groundwater.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권1호
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• pp.9-18
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• 2010

In this study, Solid-phase micro-extraction (SPME) with Gas Chromatograph using Flame Ionization Detector (GC/FID) was studied as a possible alternative to liquid-liquid extraction for the analysis of Methyl tert-butyl ether (MTBE) and Tertiary-butyl ether (TBA) in water and an optimization condition of trace analysis of MTBE and TBA using the design of experiment (DOE) was described. The aim of our research was to apply experimental design methodology in the optimization condition of trace analysis of fuel oxygenated compounds in soil-phase microextraction with GC/FID. The reactions of SPME were mathematically described as a function of parameters of Temp ($X_1$), Volume ($X_2$), Time ($X_3$) and Salt ($X_4$) being modeled by the use of the partial factorial designs, which was used for fitting 2nd order response surface models and was alternative to central composite designs. The model predicted agreed with the experimentally observed result ($Y_1$(MTBE, $R^2$ = 0.96, $Y_2$ (TBA, $R^2$ = 0.98)). The estimated ridge of the expected maximum responses and optimal conditions for MTBE and TBA were 278.13 and (Temp ($X_1$) = $48.40^{\circ}C$, Volume ($X_2$) = 73.04 mL, Time ($X_3$) = 11.51 min and Salt ($X_4$) = 12,50 mg/L), and 127.89 and (Temp ($X_1$) = $52.12^{\circ}C$, Volume ($X_2$) = 88.88mL, Time ($X_3$) = 65.40 min and Salt ($X_4$) = 12,50 mg/L), respectively.

• 한국막학회:학술대회논문집
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• 한국막학회 1997년도 추계 총회 및 학술발표회
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• pp.53-60
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• 1997

1. 서론 : 촉매막기술은 반응과 분리공정을 동시에 하나의 장치에서 수행할 수 있기 때문에 한 개의 공정을 줄일 수 있는 효과적인 에너지 절약형 기술이다. 생성물중의 적어도 하나가 선택적으로 막을 통해 투과되기 때문에 가역반응의 경우에는 비가역반응에 가까운 거동을 보이게 된다[1-5]. 본 연구는 12-텅스토인산($H_3PW_{12}O_{40}$)를 촉매로 사용하고 막반응시를 비활성촉매막반응기(IMRCF, Inert membrane reactor with catalyst in the feed side)형태, 막으로는 PSF(Polysulfone), PPO(Polyphenylene Oxide)를 사용하여 MTBE(Methyl tert-butyl ether)분해반응을 모사하였다. 막반응기에서 생성된 생성물을 선택적으로 분리해냄으로 인하여 전환율은 고정층보다 증가하였는데 반응온도가 증가할수록, 반응물의 분압은 낮을수록 증가하였다. 반응온도가 높아짐에 따라 막반응기에서의 전환율은 고정층반응에서 나타나는 전환율과의 차이가 줄어드는 것을 볼 수 있었다. 위와같은 결과에 따라서 MTBE 반응물의 분해로 생성되는Isobutene의 수율이 90$\circ$C 이상의 반응온도에서 촉매/반응물비에 대한 최적조건이 나타나는 것을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1315-1322
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• 2006

The following study describes the gas chromatography-mass spectrometry (GC-MS) based screening and confirmation analysis of urinary androgenic steroids. Four commercially available solid-phase extraction (SPE) cartridges, Serdolit PAD-1, Sep-pak $C_{18}$, amino-propyl, and Oasis HLB, and three different extractive organic solvents, diethyl ether, methyl tert-butyl ether (MTBE), and n-pentane, were tested for sample preparation. Overall, Oasis HLB combined with MTBE extraction provided the highest recoveries in 39 of 46 total androgenic steroids examined and it showed a good extraction yield (>82.1%) for polar steroids, such as metabolites of fluoxymesterone, oxandrolone, and stanozolol, which gave a poor recovery in both n-pentane (9.2-64.3%) and diethyl ether (22.2-73.6%) extractions. All SPE sorbents tested showed potential, because they were efficient in extraction for most or selective steroids. When applied to positive urine samples based on the results obtained, the present method allowed selective and sensitive analysis for detection of urinary androgenic steroids. The experiments showed that the high-resolution MS method is clearly more efficient than the low-resolution MS technique for the detection of many urinary steroids. However, comprehensive sample clean-up procedures also might be needed especially in confirmation analysis to increase detectability.