• Journal of Korean Society of Water and Wastewater
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• v.25 no.1
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• pp.63-74
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• 2011

The degradation characteristics of 2-chlorophenol(2-CP) by Ferrate(VI) were studied. The degradation efficiency of 2-CP in aqueous solution was investigated at various values of pH, Fe(VI) dosage, initial concentration and aqueous solution temperature. The maximum degradation efficiencies of 2-CP were obtained at pH 7.0 and aqueous solution temperature of 25$^{\circ}C$. The degradation efficiency was proportional to dosage of Fe(VI). Also, the initial rate constant of 2-CP degradation increased with decreasing of the 2-CP initial concentration. In addition, the degradation pathway study for 2-CP was conducted with GC-MS analysis. Acetic acid, formic acid, benzaldehyde and benzoic acid were identified as reaction intermediates of the 2-CP degradation by Ferrate(VI).

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.31-38
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• 2013

The degradation of 4-chlorophenol(4-CP) by various AOPs(Advanced Oxidation Processes) with continuous feeding of $H_2O_2$, including the ultraviolet/hydrogen peroxide, the Fenton and the photo-Fenton process has been investigated. The photo-Fenton process showed the highest removal efficiency for degradation of 4-chlorophenol than those of other AOPs including the Fenton process and the combined UV process with continuous feeding of $H_2O_2$. In the photo-Fenton process, the optimal experimental condition for 4-CP degradation was obtained at pH 3. Also the 4-CP removal efficiency increased with decreasing of the initial 4-CP concentration. 4-chlorocatechol and 4-chlororesorcinol were identified as photo-Fenton reaction intermediates, and the degradation pathways of 4-CP in the aqueous phase during the photo-Fenton reaction were proposed.

• Journal of Environmental Science International
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• v.3 no.1
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• pp.65-76
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• 1994

The regiospecific potential for the reductive dechlorination of 2-, 3-, 4-, 2, 3-, 2, 4-, and 3, 4-chlorophenols (CPs) was studied in mono- and di-CP(DCP) adapted sediment slurries(10% solids). Freshwater sediments adapted to transform 2-CP dechlorinated all tested mono- and di-CPs except 4-CP without a lag period. Adaptation to 2-CP, thus, enhanced the onset of dechlorination of 3-CP and all ortho-substituted CPs tested. Sediment adapted to transform 3-CP dechlorinated all test CPs, except 4-CP and 2, 4-DCP, without a lag period. Sediment adapted to individual DCPs (2, 3-, 2, 4-, and 3, 4-DCP_ exhibited dechlorination(no lag phase) of 2-CP, 2, 3-, 2, 4-, and 3, 4-CDP. Interestingly, meta-cleavage of 3, 4-DCP in all tested adapted sediment occurred, while para-cleavage occurred in 3, 4-DCP adapted sediment. Sediment adapted to dechlorinate ortho and meta-chlorines exhibited a preference for meta following ortho-cleavage, but not for para-cleavage, while the preference for reductive dechlorination was ortho>meta>para for mono-CPs and ortho>para>meta for DCPs in unadapted freshwater anoxic sediments.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.6
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• pp.779-786
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• 2012

The degradation of 2-chlorophenol(2-CP) by various AOPs(Advanced Oxidation Processes) including the photo-Fenton process has been examined. In sole $Fe^{2+}$, UV or $H_2O_2$ process without combination, low removal efficiencies have been achieved. But the photo-Fenton process showed higher removal efficiency for degradation of 2-chlorophenol than those of other AOPs including the Fenton process and the UV processes. In the photo-Fenton process, the optimal experimental conditions of 2-chlorophenol degradation were obtained at pH 3 and the $Fe^{2+}/H_2O_2$molar ratio of 1. Also the 2-chlorophenol removal efficiency increased with decreasing of the initial 2-chlorophenol concentration. 3-chlorocatechol and chlorohydroquinone were identified as photo-Fenton reaction intermediates, and a degradation pathway of 2-chlorophenol in the aqueous phase during the photo-Fenton reaction was proposed.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.322-325
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• 2003

The feasibility of treating 2-chlorophenol (2CP) contaminated soils with ozone venting was investigated in this research. Adding ozone to the existing air-venting process provides an alternative to achieve a complete in-situ treatment by oxidizing the contaminant in the process. A column study with artificial soil was used to simulate the venting process. Ozone concentrations at 2.4, 7.6 and 19.4 mg/L, and flow rates at 100 and 150 mL/min were used. The reaction times were 10, 20, 50, and 60 minutes. Blank samples using air venting were also run for comparison. It is obvious that ozone-venting had a much faster removal rate than air-venting. As higher concentration of ozone is applied, the reaction rate increased significantly. As higher concentration was applied, the flux of ozone to the liquid film increased. This also increased the removal rate of 2CP and therefore the breakthrough curve came out earlier.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.35-43
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• 2000

Aqueous solutions of chlorobenzene and chlorinated phenols were exposed to 200kHz ultrasound with a power of $6.0W/\textrm{cm}^2$ per unit volume on sonochemical reactor under ambient temperature and pressure conditions. The concentration of chlorobenzene and chlorinated phenols decreased with ultrasound, indicating first-order kinetics. Degradation rate constants are calculated from the slope of plots. The order of the rate constants is as follows : 2-chlorphenol(2-CP)$\leq$ 4-chlorophenol(4-CP)<3-chlorophenol(3-CP)$5.63~9.96({\times}10^{-2})min^{-1}$ under argon. The degradation was suppressed by the addition of t-BuOH and the suppressed yield was agreed with their reactivity for hydroxy radical. The main products of these systems were formic acid, acetic acid, small amount of methane and inorganic carbon forms as carbon dioxide, carbon monoxide in sonolysis of chlorinated phenols, and also these results agreed with change of TOC.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.179-185
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• 2000

In this study, we examined the movement of chlorophenol as a precursor of the dioxin in the after-combustion to minimize the creation and emission of dioxin in a municipal waste incinerator. The CPs was injected to the electric incinerator in temperature $300{\sim}500^{\circ}C$, using $N_2$ gas to control the reaction time, The oxygen quantity supplied into the $CP_s's$ isomer combustion was added with the value of experience formula. When the space velocity in reactor was 60~80/sec, the removal efficiency of CP was obtained in the presence of Mo-V catalyst and non catalyst. The efficiency in non-catalyst was 74% to 80% mono-CP, di-CP 55~66%, tri-CP 50~58%, while mono-CP 90~99.9%, di-CP 96~97%, tri-CP 76~99% in a catalyst. Consequently, it was shown that these were 20~30% more efficienct than those.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.237-241
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• 1997

Two isolated strains, Comamonas testosteroni CPW301 and Arthrobacter ureafaciens CPR706, were able to use 4-chlorophenol (4-CP) as a sole carbon and energy source. CPW301 was found to degrade 4-CP via a meta-cleavage pathway in which the chloro-substituent was eliminated even when 4-chlorocatechol was cleaved by the catechol 2, 3-dioxygenase. In contrast, CPR706 removed chloride from 4-CP prior to the ring-fission reaction, producing hydroquinone as a transient intermediate during 4-CP degradation. CPR706 exhibited much higher tolerance for 4-CP than CPW301, which was indicated by the maximum degradable concentration and degradation rate.

• Environmental Engineering Research
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• v.25 no.1
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• pp.62-70
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• 2020

Here in this work, a 4-chlorophenol (4-CP)-degrading bacterial strain Bacillus subtilis (B. subtilis) MF447840.1 was isolated from the drain outside the Hyundai car service center, Agartala, Tripura, India. 16S rDNA technique used carried out for genomic recognition of the bacterial species. Isolated bacterial strain was phylogenetically related with B. subtilis. This strain was capable of breaking down both phenol and 4-CP at the concentration of 1,000 mg/L. Also, the isolated strain can able to metabolize five diverse aromatic molecules such as 2-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, 4-nitrophenol, and pentachlorophenol for their growth. An extensive investigation was performed to portray the kinetics of cell growth along with 4-CP degradation in the batch study utilizing 4-CP as substrate. Various unstructured models were applied to evaluate the intrinsic kinetic factors. Levenspiel's model demonstrates a comparatively enhanced R² value (0.997) amongst every analyzed model. The data of specific growth rate (μ), saturation constant (K_S), and Y_X/S were 0.11 h^-1, 39.88 mg/L, along with 0.53 g/g, correspondingly. The isolated strain degrades 1,000 mg/L of 4-CP within 40 h. Therefore, B. subtilis MF447840.1 was considered a potential candidate for 4-CP degradation.

• Environmental Engineering Research
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• v.7 no.4
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• pp.227-237
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• 2002

Chemical vapor deposition (CVD), ion beam sputtering (IBS) and sol-gel method were used to prepare TiO$_2$ thin films for degradation of hazardous organic compounds exemplified by 2-chlorophenol (2-CP). The influence of supporting materials and coating methods on the photocatalytic activity of the TiO$_2$ thin films were also studied. TiO$_2$ thin films were coated onto various supporting materials including steel cloth (SS), copper cloth, quartz glass tube (QGT), and silica gel (SG). Results indicate that SS (37 μm)- TiO$_2$ thin film prepared by IBS method improves the photodegradation of 2-CP. Among all supporting materials studied, SS(37 μm) is found to be the best support.