• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.235-238
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• 2001

Monod kinetics에 관련된 주요 생분해 파라미터를 도출하기 위하여 microcosm 규모의 배치실험에서 BTEX 화합물에 대해 분해능이 우수한 Pseudomonas aeruginosa을 이용해 다양한 농도의 벤젠에 대한 분해기작을 고찰하였다. 벤젠의 생분해율(D)과 Maximumspecific growth rate ($\mu$$_{max}$)는 기질의 농도가 증가할수록 높아지다가 최고점에 도달 후에 점차적으로 감소하였으며 이것은 어느 한계점 이상의 벤젠 농도가 미생물의 생분해에 방해 요소로 작용한다는 것을 나타낸다. 그러나 미생물에 의한 벤젠 분해의 상관관계를 나타내는 yield coefficient(Y)는 벤젠의 초기 농도가 낮을수록 높은 값을 나타내었다. Microbial decay constant( b)와 half-saturation constant(K$_{c}$)는 각각 0.21~0.48day$^{-1}$와 218mg/$\ell$로서 문헌값 보다 높은 수치를 나타내었다. 실험으로부터 결정된 생분해 파라미터들은 초기 벤젠 농도에 따라 큰 차이를 보이므로 생분해 모델링에 사용할 파라미터는 기질농도에 따라 적절하게 선택되어야 한다고 사료된다.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.452-456
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• 2008

Mesoporous silicate materials have been used as adsorbents due to the advantage of high specific surface area and regular mesopores. In this study, conventional mesoporous silicates (MCM-41, and SBA-15) were utilized as adsorbents for gaseous benzene, one of volatile organic compounds. In the results of the breakthrough curves of gaseous benzene, SBA-15 showed a higher benzene adsorption capacity in adsorption condition of this study. Especially, compared to benzene adsorption of zeolite X, that of SBA-15 was higher by a factor of 2.7. With increasing adsorption temperature, adsorption capacity for benzene of SBA-15 was decreased rapidly. This indicates that benzene adsorbed weakly on SBA-15.

• Journal of the Korean Chemical Society
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• v.37 no.12
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• pp.1003-1009
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• 1993

The viscosities of benzene have been determined at several temperatures and pressures to investigate the effect of temperature and pressure on the viscosity of benzene in liquid phase. When a falling ball viscometer with a constant volume contained a given amount of liquid benzene at desired temperatures and pressures, the viscosities of benzene in the viscometer could be evaluated from the measurements of the falling time of a skinker. The variations of the specific volume and the free volume of liquid benzene with temperature and pressure were, from the results, searched out. Finally, the effects of temperature and pressure on the viscosity of benzene were discussed by means of the variations of free volume with temperature and pressure.

• Journal of the Korean Chemical Society
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• v.20 no.1
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• pp.56-58
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• 1976

A new mechanism is proposed for the reduction of nitrobenzene in basic solution that does not involve hydroxylamine as an intermediate. This paper presents evidence that the azoxybenzene is not formed from the hydroxylamine, but formed instead from the dimerization of nitrosobenzene.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2000.05a
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• pp.99-101
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• 2000

본 연구에서는 교외지역인 전남 나주에 소재한 동신대학교 1공학관 주변의 환경 대기중의 VOC중 벤젠을 계절별로 그 농도를 비교해 보았다. 그 결과 첫째, 벤젠과 톨루엔의 계절별 농도 평균값이 봄(늦봄), 여름, 가을 순으로 농도가 높게 나타나 온도에 상대적으로 많은 영향이 있음을 알 수 있었다. 둘째, 나주지역의 벤젠농도가 여천지역이나 서울지역에 비해 봄에 8배, 3배 그리고 여름철에 14배, 5배 정도로 각각 낮게 나타나 나주 지역이 비교적 청정지역임을 알 수 있었다.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.127-130
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• 2004

벤젠과 사이클로헥산을 투과증발법을 이용하여 분리하는 경우에는, 벤젠과 사이클로헥산의 물리적 성질이 비슷하고, 그 끓는점이 매우 비슷하기 때문에, 물리화학적인 특성을 먼저 알아야 한다. 벤젠은 이중결합을 가지고 있고, 공명구조를 이루고 있다. 즉 극성기와 강한 상호작용을 할 수 있는 파이전자를 벤젠이 가지고 있음을 주목하여야 한다.(중략)

• Journal of the Korean Chemical Society
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• v.24 no.4
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• pp.302-309
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• 1980

The solubilities of n-propyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene have been measured at 19, 25 and $40^{\circ}C$ in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of n-propyl bromide in nitrobenzene is greater than in 1,2,4-trichlorobenzene, indicating a stronger interaction of n-propyl bromide with nitrobenzene than with 1,2,4-trichlorobenzene. In the presence of gallium bromide, 1: 1 complex $n-C_3H_7Br\cdotGaBr_3$ is formed in the solution. The instability constant K of the complex was evaluated. $$n-C_3H_7Br\cdotGaBr_3 \rightleftarrows n-C_3H_7Br ＋ \frac{1}{2Ga_2Br_6 }$$The change of enthalpy, free energy and entropy for the dissociation of the complex were also calculated. It seems that the stabilities of the complex, gallium bromide with alkyl bromide, are relatively concerned with the stabilities of the alkyl ion.

• Clean Technology
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• v.20 no.3
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• pp.256-262
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• 2014

Catalytic oxidation characteristics of benzene as a VOC was investigated in a fixed bed flow reactor using $Cu/{\gamma}-Al_2O_3$ catalyst. The parametric tests were conducted at the reaction temperature range of $200{\sim}500^{\circ}C$, benzene concentration of 400~650 ppm, gas flow rate of 50~100 cc/min, and space velocity range of $7,500{\sim}22,500hr^{-1}$. The property analyses by using the BET, SEM, TGA and the conversion of catalytic oxidation of benzene were examined. The experimental results showed that the conversion was increased with decreasing benzene concentration, gas flow rate and space velocity. Benzene oxidation reaction over $Cu/{\gamma}-Al_2O_3$ catalyst could be expressed as the first order homogeneous reaction of which the activation energy was 17.2 kcal/mol and frequency factor was $1.33{\times}10^6sec^{-1}$.

• Journal of the Korean Chemical Society
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• v.15 no.5
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• pp.228-235
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• 1971

The solubilities of n-butyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene have been measured at $19^{\circ},\;25^{\circ},\;and\;40^{\circ}C$ in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of n-butyl bromide in nitrobenzene is greater than in 1,2,4-trichlorobenzene, indicating a stronger interaction of n-butyl bromide with nitrobenzene than with 1,2,4-trichlorobenzene. In the presence of gallium bromide, complex of n-butyl bromide with gallium bromide, 1:1 complex, $n-C_4H_9Br{\cdot}GaBr_3$, is formed in the solution. The instability constant K of the complex was evaluated. $n-C_4H_9Br{\cdot}GaBr_3{\rightleftharpoons}n-C_4H_9Br+\frac{1}{2}Ga_2Br_6$ The changes of enthalpy, free energy and entropy for the dissociation of the complex were also calculated.

• Journal of Soil and Groundwater Environment
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• v.8 no.1
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• pp.42-47
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• 2003

A biofilter study was performed in order to remove mixed benzene and ethylene emitted from soil and groundwater remediation. In particular, more than 96% of ethylene was removed at residence times of 10～15 min, and the possibility of use of the biofilter was obtained. The benzene removal efficiency was achieved as much as 100% at residence times of 2～15 min. With a residence time of 15 min, the maximum elimination capacity of benzene and ethylene was 4.3 g/$\textrm{m}^3$hr and 1.4 g/$\textrm{m}^3$hr, respectively. The maximum elimination capacity of benzene was 3 times higher than that of ethylene. Carbon dioxide concentration decreased as residence times were lowered due to low ethylene degradation rate. The maximum carbon dioxide production rate of 3,169 [mg-$CO_2$/(g-${C_2}{H_4}$＋${C_6}{H_6$)] was investigated when benzene and ethylene were completely removed. It was found that dominant bacteria in the benzene-degrading microorganisms were identified as Bacillus mycoides and Pseudomonas fluorescens. Dominant bacteria in the ethylene-degrading microorganisms were identified as Pseudomonas putida and Pseudomonas fluorescens.