• Korean Journal of Environmental Biology
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• v.22
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• pp.71-77
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• 2004

Alkylphenols (8), chlorophenols (2), bisphenol A, eoprostanols (2) and cholesterol compounds were analyzed in the surface water and surface sediment taken from Gwangyang Bay and surrounding streams in 2001. Among the target analytes, nonylphenol and dihydrocholesteyol compounds were detected with high concentration and high frequency. t-Octylphenol, bisphenol A and coprostanols were detected only in some sediment samples from the stream. The highest concentration of nonylphenol was determined in stream sample, and concentrations of nonylphenol in the inner part of Gwangyang Bay were higher than those in the out part. Nonylphenol concentrations in the surface seawater and surface sediment samples ranged from 4.0 to 74.0 ng l$\^$-1/ and from 3.1 to 74.3 ng g$\^$-1/ dry wt., respectively. Partition coefficient (LogK$\_$oc/) of nonylphenol between sediment and water was 4.8. Nonylphenol nnd dihydrocholesteol concentrations in the stream surface sediment samples ranged from 4.6 to 808.6 and from 78.4 to 1133.6 ng g$\^$-1/ dry wt., respectively. Relatively high concentrations of nonylphenol were found in the stream samples which aye flowing through industrial complex area, while dihydrocholesterol concentration was relatively high in the stream samples which are flowing through only municipal area. Seaward decreasing tyend in nonylphenol concentration was observed from the Seomjin River estuary to the Gwanyang Bay. Such trend was best supported by the strong correlation between nonylphenol concentration and salinity in water samples.

• Journal of environmental and Sanitary engineering
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• v.22 no.2
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• pp.9-20
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• 2007

The incineration process has commonly used for wastes amount reduction and thermal treatments of pollutants as the technologies accumulated. However, the process is getting negative public images owing to matter of hazardous pollutants emission. Specially dioxins became a main issue and were mostly emitted from municipal solid wastes incineration. In this reason, pyrolysis/gasification/melting process is presented as an alternative of incineration process. The pyrolysis/gasification/melting process, a novel technology, is middle of verification of commercial plant and development of technologies in Korea. But the survey about the pollutant emission from the process, and background data in these facilities is necessary. So in this survey, t is investigated that the behavior of chlorobenzenes and chlorophenols in plasma type pyrolysis/gasification/melting plant of pilot scale. We investigated discharging behavior of each phase of chlorobenzene through each process in the plsasma type pyrolysis/gasification/melting process. From this result, it was found that about 99 percent of particle-phase chlorobenzene was removed, but on the other hand gas-phase chlorobenzene was increased by about 600 percent through heat exchanger, flue gas cooling, system and semi dry absorption bag filter(SDA/BF). Also, this investigation presented that di-chlorobenzene(DCB) tri-chlorobenzene(TCB), tetra-chlorobenzene(TeCB), penta-chlorobenzene (PCB), except mono-chlorobenzene(MCB) and hexa-chlorobenzene(HCB) were increased through the flue gas cooling system and the semi dry absorption bag filter(SDA/BF). It was investigated that concentration of particle-phase chlorophenol was decreased by about 66 percent, but on the other hand, concentration of gas-phase chlorophenol was increased by about 170 percent through heat exchanger, flue gas cooling system, and semi dry absorption bag filter(SDA/BF). Also, it was found that di-chlorophenol(DCP), tri-chlorophenol(TCP), and penta-chlorophenol(PCP) were increased through the flue gas cooling system, and the semi dry absorption bag filter(SDA/BF). It can be considered that small-scale pilot facility and short investigation period might cause the concentration increase through the flue gas cooling system and the semi dry absorption bag filter(SDA/BF). A further study on real-scale pilot facility and accurate investigation may be required.

• Analytical Science and Technology
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• v.12 no.1
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• pp.68-74
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• 1999

The Concentrations of PCDDs/PCDFs and their precusors(chlorophenols, chlorobenzenes, PCB) were analyzed from the dioxin control device such as EP and SCR to know the emission patterns of these compounds and find the dioxin index compounds. The dioxin concentration increased 7 times in outlet part than inlet part of EP and the concentration of CBs, CPs and PCBs also were increased through this control device. These phenomia may be related to the operating temperature of Electroprecipitator(EP), which the operating temperature is near the $300^{\circ}C$, the method of the decreasing the operating temperature need to consider to prevent the formation of these compounds. In the selected catalytic reactor with wet scrubber(SCR+WS), these compounds were removed after passing the device over 90% for CPs, 30~40% for CBs and 60% for PCBs. But, the systematic study have to perform to reduce the formation of PCDDs/PCDFs and precusors.

• Analytical Science and Technology
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• v.18 no.4
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• pp.320-328
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• 2005

The most common five chlorophenols (4-chloro-3-methylphenol, 2,4,5-trichlorophenol, 2,4,6-trichlorophenol, 2,3,4,6-tetrachlorophenol, pentachlorophenol) were determined from the industrial wastewater by GC/MS. The samples were collected from the petrochemical company, textile company and leather making company. The developed analytical method was modified by USEPA Method 3510. The samples were extracted with dichloromethane under pH 2 and pH 5-6, and determined by the GC/MS with SIM mode. There were good linearities (above $R^2=0.9943$) on e ranges of the 0.1 ng/mL~10 ng/mL and 0.5 ng/mL~10 ng/mL, and the limit of detection were between 0.1 ng/mL and 0.5 ng/mL. The absolute recoveries were measured at the concentration of 1, 5, and 10 ng/mL, and the recovery was 71.6~98.9% except for PCP. The relative standard deviation (RSD) was 1.2~14.3% and it gave a good reproducibility for the assay. The bias, which shows the accuracy, was a good although it was a little high values (11.3~22.1%) at the low concentration (1 ng/mL).

• Analytical Science and Technology
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• v.15 no.3
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• pp.196-213
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• 2002

The alkylphenols, chlorophenols and bisphenol A were determined by gas chromatography/mass spectrometry-selected ion monitoring mode followed by three work-up methods for comparison; EPA method, isoBOC derivatization method and TBDMS derivatization method. Eleven phenols in water samples were extracted with dichloromethane. Also, solid-phase extraction (SPE) with XAD-4 and subsequent conversion to isobutoxycarbonyl derivatives or tert.-butyldimethylsilyl derivatives for sensitive analysis with the selected ion-monitoring (SIM) mode. The recoveries were 85.1~109.9% (EPA method) and 90.3~126.6% (isoBOC derivatization and TBDMS derivatization), respectively. The method detection limit of bisphenol A for SIM were 0.732 ${\mu}g/{\ell}$ (EPA method), 0.002 ${\mu}g/{\ell}$ (isoBOC derivatization) and 0.021 ${\mu}g/{\ell}$ (TBDMS derivatization). The SIM responses were linear with the correlation coefficient varying 0.9755~0.9981 (isoBOC derivatization), and 0.9908~0.9996 (TBDMS derivatization). When these methods were applied to treated wastewater sample from a polyethylene plant, the concentrations of 11 phenols were below the method detection limit.

• Journal of Soil and Groundwater Environment
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• v.10 no.4
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• pp.62-69
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• 2005

Removal of 4-chlorophenol (4CP) by natural manganese dioxide (NMD) catalyzed reaction was investigated in this study. Tests were also carried out to evaluate the effects of pH and natural organic matter (NOM) on the degradative oxidation of 4CP. Experimental results proved that NMD was effective for the removal of 4CP. Extensive kinetic analysis suggests that overall oxidation of 4CP by NMD is second-order reaction, the first-order with respect to 4CP, and the first-order with respect to NMD, respectively. Also, 4CP oxidation rates on the Mn-oxide surfaces were highly dependent upon experimental conditions such as pH, initial concentration of 4CP or NMD, and existence of humic acid. As pH increased above PZC of NMD, the reaction rate of 4CP was decreased, due to the low affinity of 4CP on NMD at high pH. At pH lower than PZC of NMD, reaction rate of 4CP was also decreased. It was considered that humic acid was involved in the oxidative coupling reaction of 4CP by NMD, resulting in the enhanced degradation rate of 4CP. This study proved that natural manganese oxide can be effectively applied for the removal of chlorophenols in aqueous phase.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.1
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• pp.88-95
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• 1998

The Electron/Hole Pair is generated when the Activation Energy produces by Ultraviolet Ray illumination to the Semiconductor. And $OH^-$ ion produces by Water Photo-Cleavage reacts with Positive Hole. As a result, OH Radical acting as strong oxidant is generated and then Photocatalytic Oxidation Reaction occurs. The Photocatalytic Oxidation can oxidize the chlorophenol to Chloride and Carbon Dioxide easier, safer and shorter than conventional Water Treatment Process With the same degree of chlorination, the $Cl^-$ ion at para (C4) position is most easily replaced by the OH radical. And then, the blocking effect of $OH^-$ ion between the $Cl^-$ ions and $Cl^-$ ions at symmetrical location is easily replaced by the OH radical. For mono-, di-, tri-chlorophenols, there is no obvious difference in decomposition rate, decomposition efficiency and completeness of the decomposition reaction except for 2,3-dichloropheno, 2,4,5-, 2,3,4-trichlorophenol. The decomposition efficiency is higher than 75% and completeness of the decomposition reaction is higher than 70%. Therefore, continuous flow photocatalytic reactor is promising process to remove the chlorinated aromatic compounds which is more toxic than non-chlorinated aromatic compound.

• Environmental Engineering Research
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• v.13 no.4
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• pp.216-223
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• 2008

An efficient method for the simultaneous determination of eleven phenolic endocrine-disrupting chemicals (EDCs) present in wastewater influent samples was described. The 11 phenolic EDCs including alkylphenols, chlorophenols, and bisphenol A were determined by gas chromatography/mass spectrometry-selected ion monitoring (GC/MS-SIM) following two work-up methods for comparison; isobutoxycarbonyl (isoBOC) derivatization and tert-butyldimethylsilyl (TBDMS) derivatization. The wastewater influent samples containing the 11 EDCs were adjusted to pH 2 with $H_2SO_4$ and then cleaned up with n-hexane. Next, they were subjected to solid-phase extraction (SPE) with XAD-4 resin and subsequently converted to isoBOC or TBDMS derivatives for sensitivity analysis with gas chromatography/mass spectrometry-selected ion monitoring (GC/MSSIM). Following isoBOC derivatization and TBDMS derivatization, the recoveries were 86.6-105.2% and 97.6-142.7%, the limits of quantitation (LOQ) for the 11 phenolic EDCs for SIM was 0.001-0.050 ng/mL and 0.003-0.050 ng/mL, and the SIM responses were linear with the correlation coefficient varying by 0.9717-0.9995 and 0.9842-0.9980, respectively. When these methods were applied to five selected wastewater influent samples, for isoBOC derivatization and TBDMS derivatization the ranges of concentration detected were 0.2-99.6 ng/mL and 0.4-147.4 ng/mL, respectively.

• Journal of Environmental Science International
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• v.16 no.1
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• pp.9-19
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• 2007

Comparing predicted PCDF isomer patterns with those obtained from a municipal waste incinerator assessed the role of two-phenol condensation pathways in the formation of PCDFs. Complete PCDF homologue and isomer distributions were obtained from a Fluidized Bed Incinerator (FBI). Two-phenol condensation model, dependent only on the distributions of phenols, was developed to predict the PCDF congeners produced from phenol precursors. R-squared values from linear correlations are presented for the dichlorinated through hexa-chlorinated isomer distributions between measured and predicted. They range from 0.00: to 0.1 far the di-chlorinated through hexa-chlorinated isomer sets. Agreement between predicted and measured PCDF isomer distributions was very poor for all homologues. Two-phenol condensation pathways are not likely to be the pre-dominant pathways in the formation of PCDF in a FBI. However, dibenzofuran (DF) is likely to be produced from a condensation of two phenols. This work demonstrates the use of PCDF homologue and isomer patterns for testing PCDF formation mechanism from two-phenol condensation pathways in municipal waste incinerators.

• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.468-472
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• 2012

Efficient one-pot microwave-assisted synthesis of various benzo-[1,4]-oxazinones via Smiles rearrangement is described. Treatment of 2-chloroacetamide, substituted 2-chlorophenols and cesium carbonate in MeO-PEG-OMe (2,000) as solvent afforded the corresponding benzo-[1,4]-oxazinones and 1H-pyrido[2,3-b][1,4]-oxazin-2-(3H)-one as moderate yield.