• Journal of the Korean GEO-environmental Society
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• v.23 no.10
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• pp.5-12
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• 2022

In this study, we investigated the UV/H₂O₂ process to treat organic compound-spilled water. In consideration of usage and properties, benzene, toluene, phenol, and methyl ethyl ketone were selected as representative organic compounds. The selected material was first removed by natural volatilization and aeration that simulated the pretreatment of the prcoess. After that, UV/H₂O₂ oxidation experiments were conducted under various H₂O₂ concentration conditions. Benzene and toluene were mostly volatilized before reaching the oxidation process due to high volatility. Considering the volatility, oxidation experiments were performed at an initial concentration of 5 mg/L for benzene and toluene. The UV/H₂O₂ oxidation process achieved 100% of benzene and toluene removal after 20 minutes under all hydrogen peroxide concentration conditions. The phenol was rarely removed from the volatile experiments and oxidation tests were performed at an initial concentration of 50 mg/L. The process showed 100 % phenol removal after 30 minutes under 0.12 v/v% of hydrogen peroxide concentration condition. Methyl ethyl ketone was removed 58 % after 2 hours of volatile experiments. The process showed 99.7% Methyl ethyl ketone removal after 40 minutes under 0.08 v/v% of hydrogen peroxide concentration condition. It was confirmed that the UV/H₂O₂ process showed high decomposition efficiency for the four selected organic compounds, and identified the amount of hydrogen peroxide in classified organic contaminants.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2002.05a
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• pp.10-14
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• 2002

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.169-174
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• 2017

Acute and chronic toxicities of methyl ethyl ketone and methanol were investigated on Paronychiurus kimi (Collembola), for evaluating the potential effects of accidental exposures of these chemical substances on the terrestrial environments. This study was undertaken to establish a toxicity database for these chemical substances, which was required for the preparation of the response compensation and liability act for agricultural production and environmental damage. The 7-d acute toxicity and 28-d chronic toxicity were conducted using the OECD artificial soil spiked with varying, serially diluted concentrations of methyl ethyl ketone and methanol. Mortality was recorded after 7-d and 28-d of exposures, and the number of juveniles were determined after 28-d of exposure in the chronic toxicity test. In both assessments, methanol was more toxic than methyl ethyl ketone in terms of mortality ($LC_{50}$) and reproduction ($EC_{50}$). The 7-d $LC_{50}$ of methyl ethyl ketone and methanol were 762 and $2378mg\;kg^{-1}$ soil dry wt., respectively, and the 28-d $LC_{50}s$ were 6063 and $1857mg\;kg^{-1}$ soil dry wt., respectively. The 28-d $EC_{50}$ of methyl ethyl ketone and methanol were 265 and $602mg\;kg^{-1}$ soil dry wt., respectively. Comparison of results obtained in this study with literature data revealed that P. kimi was more sensitive to methanol than other soil invertebrates. However, given the high volatility of the chemicals tested in this study, further studies are necessary to improve the current test guideline, or to develop new test guidelines for an accurate assessment of chemicals that require toxicity databases for chemical accidents.

• Clean Technology
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• v.23 no.4
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• pp.421-428
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• 2017

In this study, we have investigated the characteristics of adsorption and desorption of toluene, methyl ethyl ketone (MEK) and their binary component using activated carbon. The BET analysis was performed to identify the characteristics of the activated carbon, and the desorption characteristics with temperature were examined to find out an optimum desorption temperature. Ten cyclic experiments of adsorption-desorption were performed, where each adsorption temperature was maintained at room temperature and desorption temperature at upto $120^{\circ}C$. In case of single component cyclic test, the efficiencies of adsorption and desorption decreased as the cycle increased. MEK which has lower affinity with activated carbon than toluene showed lower efficiencies of adsorption and desorption. In case of binary component cyclic test, a typical roll-up phenomenon was observed during adsorption process, where MEK reaches at breakpoint first and then was swept out by toluene.

• Journal of Radiation Protection and Research
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• v.9 no.2
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• pp.103-111
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• 1984

A convenient method of $^{99m}Tc$-methyl-ethyl-ketone (MEK) extraction technique was developed and a mobile $^{99m}Tc$-extraction generator was designed. The MEK extraction and the phase separation of $^{99m}TcO^-{_4}$ were carried out with a simple procedure in the same container. The shielding of $^{99}Mo$ radioactivity was made with one lead container. The system was simplified by shielding $^{99m}TcO_4{^-}({\gamma}_e=0.14\;MeV)$ separately. $^{99m}TcO^-{_4}\;in\;^{99m}Tc-MEK$ extract was recovered by adsorption and elution only, and therefore, the possibility of volatilization was reduced. The volume of $^{99m}TcO^{-}{_4}$-saline product was reduced to 1 ml by using a small alumina column and the column operation time was shortened. The separation time of $^{99m}Tc$ was reduced to 30 minutes, and the operation was carried out at the outside of the shielding. The system was designed to operate under the condition of bacteria-free.

• Journal of the Korean Society of Safety
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• v.20 no.4 s.72
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• pp.34-39
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• 2005

To evaluate characteristics of explosion hazard of Methyl Ethyl Ketone Peroxide, MCPVT was used for this study. In result maximum explosion pressure and maximum explosion pressure rising velocity of MEK-PO were $12.1kgf/cm^2\;and\;106.81kgf/cm^2/s$. As a result or adding metal powder to estimate hazard of explosion, the maximum explosion pressure and maximum explosion pressure rising velocity according to adding Fe powder in MEK-PO increased. In opposite, those decreased resulting in adding Ca powder in MEK-PO.

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.92-96
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• 1995

The flash point is generally used as a hazardous index of fire or explosion of a flammable liquid. In this study, the lower flash points and the upper flash points according to the composition of Toluene-o-Xylene and Toluene-Methyl Ethyl Ketone mixtures are determined by air-blowing method. As results, relations between the flash points and the compositions of mixtures ; (1) for Toluene-o-Xylene mixtures $T_{fL}$=25.23 $\alpha$ ＋5.34 $T_{fu}$=27.36 $\alpha$ ＋40.50 (2) for Toluene-Methyl Ethyl Keton mixtures $T_{fL}$=10.00 $\beta$-5.00 $T_{fu}$=16.91 $\beta$＋20.45.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.06a
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• pp.22-26
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• 1998

토양오염 정화방법의 하나인 토양증기추출법(soil vapor extraction, SVE)은 오염된 토양에 진공 또는 가압의 공기를 공급하여 연속적인 공기 흐름을 유도함으로써 토양의 기공에 잔류하는 유해화합물의 증발을 촉진하여 오염물질을 제거하는 공정이다. 본 연구에서는 토양증기추출법의 효율에 영향을 주는 인자들 가운데에서 토양의 수분함량과 오염물질의 종류가 오염물질의 제거효율에 미치는 영향에 대한 실험과 계산을 수행하였다. 인공토양으로 glass bead, sand, molecular sieve가 사용되었으며. 오염물질로는 톨루엔. 메틸에틸케톤, 트리클로로에틸렌이 사용되었다. 각 실험에 대하여 프로인들리히 등온식과 기공확산모델 등을 고려하여 계산을 수행한 결과, 수분이 없는 경우에는 탈착식에 의해, 수분이 있는 경우에는 interparticle에서의 확산 현상에 의해 오염물질의 제거속도가 지배됨을 알 수 있었다. 이러한 연구결과는 정화대상지역에 SVE를 이용한 적절한 정화방법을 설계하는데 기초자료로 이용할 수 있을 것이다.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.123-127
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• 2017

To determine their acute toxicities on the earthworm (Eisenia fetida), six toxic chemicals were evaluated, according to the OECD guideline 207: sulfuric acid, methanol, methylethylketone, nitric acid, formic acid, and toluene. Sulfuric acid exhibited the maximum toxicity. The $LC_{50}$ values of sulfuric acid, nitric acid, formic acid, and toluene were 20.5, 49.1, 55.5, and $534.5{\mu}g\;cm^{-2}$, respectively. Toluene showed 26-fold lower toxicity than sulfuric acid. In this study, methanol and methylethylketone did not exhibit any toxicity to the earthworm. Further evaluation revealed that nitric acid, formic acid, and toluene exerted a change in the body weight of the chemically treated earthworms, whereas the other chemicals were ineffective. These results can be used for environmental risk assessment, when the chemicals are accidently discharged into the environment.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.101-114
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• 1998

Soil vapor extraction (SVE) is known to be an effective process to remove the contaminants from the soils by enhancing the vaporization of organic compounds using forced vapor flows or applying vacuum through soils. Experiments are carried out to investigate the effects of the organic contaminants, types of soils, and water contents on the removal efficiency with operating time. In the study, simulated soils include the glass bead which has no micropore, sand and molecular sieve which has a large volume of micropores. As model organic pollutants, toluene, methyl ethyl ketone, and trichloroethylene are selected. Desorption experiments are conducted by flowing nitrogen gas. Under the experimental conditions, it is found that there are linear relationships between logarithm of removal efficiency and logarithm of number of pore volumes. The number of pore volumes are defined as the total amount of air flow through the soil column divided by the pore volume of soil column. For three organic compounds studied, the removal rate is slow for no water content, while the number of pore volumes for removal of organic compounds are notably reduced for water contents up to 37%. For the removal of dense organic compound, such as trichloroethylene, a large number of pore volumes are needed. Also, the effects of the characteristics of simulated soils on the removal efficiency of organic compounds are studied. After the characterization of soil surface, porosity of soil columns and types of contaminants, the results could provide a basis for the design of SVE process.