• Journal of the Korean Chemical Society
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• v.57 no.4
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• pp.425-431
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• 2013

Oxidation of glutamic acid is performed in aqueous acid media at $30^{\circ}C$ under the kinetic condition [glutamic acid]$_T{\gg}[Cr(VI)]_T$. Effect of combination of micellar catalyst (SDS, TX-100) and promoter (PA, bpy, phen) has been studied. Among the promoters phen accelerates the reaction most in aqueous media. But the rate acceleration is small in the case. Combination of promoter and catalyst produces much better result. Maximum rate enhancement occurs in presence of the combination of bpy and SDS.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.139-144
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• 2003

1, 4-dioxane is a recalcitrant pollutant found in contaminated ground waters and industrial effluents. Conventional water treatment techniques are limited to treat this compound effectively. In this study, $O_3$／$H_2O_2$ oxidation process was used to eliminate 1, 4-dioxane in water and to enhance the biodegradability. Several factors affecting biodegradability enhancement were investigated. The relationship between initial oxidation rate of 1 A-dioxane and BOD enhancement rate has been determined, a kinetic model has been proposed. $H_2O_2$ concentration and pH had a proportional relation with biodegradability of 1, 4-dioxane, but in case of ozone, there was no relationship with biodegradability. 1, 4-Dioxane removal efficiencies had good agreement with the biodegradability.

• Environmental Engineering Research
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• v.11 no.1
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• pp.28-32
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• 2006

The degradation of atrazine was explored using UV alone, $H_2O_2/UV$, oxalate/UV and oxalate-assisted $H_2O_2/UV$. The addition of oxalate to the $H_2O_2/UV$ (oxalate-assisted $H_2O_2/UV$) process was the most effective method for the degradation of atrazine. The overall kinetic rate constant was split into the direct oxidation due to photolysis and that by the radicals from hydrogen peroxide or oxalate. In semi-empirical terms, the initial concentration of hydrogen peroxide had a greater contribution than that of oxalate for atrazine oxidation.

• Journal of the Korean Electrochemical Society
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• v.17 no.3
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• pp.179-186
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• 2014

Methanol electro oxidation on the surface of carbon paste modified by $NiCl_2/6H_2O$ was studied in 1M NaOH by potentiostatic and potentiodynamic methods. Ni/C catalyst by the concentration of 5% Ni showed about twice higher electro catalytic activity than Ni metal. The amount of monolayer's on the surface of electrode is almost one order higher for Ni/C than Ni electrode. The kinetic parameters and the diffusion coefficient of methanol were derived from chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) measurements.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.111-116
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• 2014

The kinetics and mechanism of oxidation of sulfanilic acid by N-chloro-p-toluene sulfonamide (chloramine-T) have been studied in acid medium. The species of chloramine-T were analysed on the basis of experimental observations and predominantly reactive species was taken into account for proposition of most plausible reaction mechanism. The derived rate law (1) conforms to such a mechanism. $$-\frac{d[CAT]}{dt}=\frac{kK_1[RNHCl][SA]}{K_1+[H^+]}$$ (1) All kinetic parameters were evaluated. Activation parameters such as energy and entropy of activation were calculated to be $(61.67{\pm}0.47)kJmol^{-1}$ and $(-62.71{\pm}2.48)kJmol^{-1}$ respectively employing Eyring equation.

• Bulletin of the Korean Chemical Society
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• v.5 no.1
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• pp.41-44
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• 1984

The oxidation of carbon monoxide has been investigated on Ni-doped ${\alpha}-Fe_2O_3$ catalyst at 300 to $450^{\circ}$. The oxidation rates have been correlated with 1.5-order kinetics; first with respect to CO and 1/2 with respect to $O_2$. Carbon monoxide is adsorbed on lattice oxygen of Ni-doped ${\alpha}-Fe_2O_3$, while oxygen appears to be adsorbed on oxygen vacancy formed by Ni-doping. The conductivities show that adsorption of CO on O-lattice produces conduction electron and adsorption of $O_2$ on O-vacancy withdraws the conduction electron from vacancy. The adsorption process of CO on O-lattice is rate-determining step and dominant defect of Ni-doped ${\alpha}-Fe_2O_3$ is suggested from the agreement between kinetic and conductivity data.

• Bulletin of the Korean Chemical Society
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• v.9 no.2
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• pp.81-84
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• 1988

The CO oxidation was performed on $H_2$-reduced NiO-${\alpha}-Fe_2O_3$ in the temperature range 150-$250^{\circ}C$. The kinetic study and the conductivity measurements indicate the oxidation reaction follows Langmuir-Rideal type process that is uncommon in heterogeneous catalyst$^1$. No active site is found on the catalyst surface for CO adsorption, but an oxygen vacancy adsorbs an oxygen, and this step is rate initiation. The partial orders are half for $O_2$ and first for CO, respectively. Apparent activation energy for over-all reaction is 9.05 kcal/mol.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.448-460
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• 2018

Copper nanoparticle-doped and graphitic carbon nanofibers-covered porous carbon beads were used as an efficient catalyst for treating synthetic phenolic water by catalytic wet air oxidation (CWAO) in a packed bed reactor over 10-30 bar and $180-230^{\circ}C$, with air and water flowing co-currently. A mathematical model based on reaction kinetics assuming degradation in both heterogeneous and homogeneous phases was developed to predict reduction in chemical oxygen demand (COD) under a continuous operation with recycle. The catalyst and process also showed complete COD reduction (>99%) without leaching of Cu against a high COD (~120,000 mg/L) containing industrial wastewater.

• Particle and aerosol research
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• v.4 no.2
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• pp.51-67
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• 2008

In this study, we devoted to kinetic measurement of the catalytic oxidation of iron-containing flame soot particles and better understanding the role of catalytic particles on carbon oxidation in particular at low temperature, targeting on autothermal regeneration of diesel particulate filter by diesel exhaust gas. Carbon-based Fe-containing particles generated by spraying ferrocene-doped diesel fuel in an oxy-hydrogen flame are tested and compared with a commercial carbon black powder for thermogravimetric analysis (TGA), secondary ion mass spectrometry (SIMS), Fourier-transform infrared spectroscopy (FTIR), Induced coupled plasma-Atomic emission spectroscopy (ICP-AES), and High-resolution transmission electron microscopy (HR-TEM). As a result, we found that a small amount of the ferrocene addition led to significant reductions in a on-set temperature and an activation energy of the carbon oxidation as well. An oxygenated surface complex forming at the particle surface could be thought as active species that would be readily consumed in particular at low temperature.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3544-3550
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• 2012

Cetrizine dihydrochloride (CTZH) is widely used as an anti-allergic drug. Sodium N-bromo-p-toluenesulfonamide or bromamine-T (BAT) is the bromine analogue of chloramine-T (CAT) and is found to be a better oxidizing agent than CAT. In the present research, the kinetics of oxidation of CTZH with BAT in acid and alkaline media was studied at 313 K. The experimental rate laws obtained are: -d[BAT]/dt=$k[BAT][CTZH]^{0.80}[H^+]^{-0.48}$ in acid medium and -d[BAT]/dt=$k[BAT][CTZH]^{0.48}[OH^-]^{0.52}[PTS]^{-0.40}$ in alkaline medium where PTS is p-toluenesulfonamide. Activation parameters and reaction constants were evaluated. The solvent isotope effect was studied using $D_2O$. The dielectric effect is positive. The stoichiometry of the reaction was found to be 1:1 and the oxidation products were identified as 4-chlorobenzophenone and (2-piperazin-1-yl-ethoxy)-acetic acid in both media. The rate of oxidation of CTZH is faster in acid medium. Suitable mechanisms and related rate laws have been worked out.