Electro-catalytic Removal of Water Pollutants by Silver-ACF from Piggery Waste

Won Chun Oh 한국공업화학회 2005 Journal of Industrial and Engineering Chemistry Vol.11 No.5

Removal Efficiency of the Pollutants from Piggery Wastes with Activated Carbon Treated with Metal and Their Pilot Scale Design

Won-Chun Oh,Chong-Sung Park,Jang-Soon Bae,Young-Shin Ko 한국탄소학회 2006 Carbon Letters Vol.7 No.3

The treatment of piggery wastes was carried out at pilot scale using a multilayered metal-activated carbon system followed by carbon bed filtration. The physicochemical properties were obtained from treated samples with aqueous solutions containing metallic ions such as Ag+, Cu2+, Na+, K+ and Mn2+, which main obsevations are subjected to inspect surface properties, color removal properties by Uv/Vis and EDX. Multilayered metal-activated carbons were contacted with waste water to investigation of the simultaneous catalytic effect for the COD, BOD, T-N and T-P removal. The removal results for the piggery waste using multilayered metal-activated carbon bed was achieved the satisfactory removal performance under permitted values of Ministry of Environment of Korea. The high efficiency of the multilayered metal-activated carbon bed was determined by the performance of this material for trapping, catalytic effect and adsorption of organic solid particles.

Characterization and hydrogen generation of Zn-containing fullerene

Won Chun Oh,Ah- Reum Jung,Weon-Bae Ko 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.3

In this study, the structural variations, surface states and mass transformation of fullerene [C60] derivatives are investigated through the preparation of an oxidized fullerene [C60O] and a Zn-containing fullerene compared to pristine fullerene [C60]. These were synthesized by an improved oxidation method using 3-chloroperbenzoic acid. From the XRD data, weak peaks of metallic zinc with pristine fullerene [C60] peaks were observed in the X-ray diffraction patterns for the Zn-containing fullerene. SEM micrographs for the metallic Zn-containing fullerene indicated that practically all the zinc introduced was located onto the carbon cages and consequently, it was dispersed into very small crystallites with growth of zinc metals. From the MALDITOF mass spectra, the differences in the spectra recorded on two types of fullerenes are due to the oxidation including chemical bonding and interposing of metallic zinc in the fullerene [C60] molecules. The FT-IR spectra gave additional information on the functional components on the surfaces of the Zn-containing fullerene. The EDX spectrum of Zn-containing fullerene showed the presence of C and O with strong Zn peaks. From the H2 gas generation result, it is considered that a KOH concentration in the Zn-containing fullerene is a helpful factor in the hydrogen generation performance. A satisfactory hydrogen generation performance was achieved on a Zn-containing fullerene treated with an increase of KOH the concentration. In this study, the structural variations, surface states and mass transformation of fullerene [C60] derivatives are investigated through the preparation of an oxidized fullerene [C60O] and a Zn-containing fullerene compared to pristine fullerene [C60]. These were synthesized by an improved oxidation method using 3-chloroperbenzoic acid. From the XRD data, weak peaks of metallic zinc with pristine fullerene [C60] peaks were observed in the X-ray diffraction patterns for the Zn-containing fullerene. SEM micrographs for the metallic Zn-containing fullerene indicated that practically all the zinc introduced was located onto the carbon cages and consequently, it was dispersed into very small crystallites with growth of zinc metals. From the MALDITOF mass spectra, the differences in the spectra recorded on two types of fullerenes are due to the oxidation including chemical bonding and interposing of metallic zinc in the fullerene [C60] molecules. The FT-IR spectra gave additional information on the functional components on the surfaces of the Zn-containing fullerene. The EDX spectrum of Zn-containing fullerene showed the presence of C and O with strong Zn peaks. From the H2 gas generation result, it is considered that a KOH concentration in the Zn-containing fullerene is a helpful factor in the hydrogen generation performance. A satisfactory hydrogen generation performance was achieved on a Zn-containing fullerene treated with an increase of KOH the concentration.

Electro-chemical preparation of TiO2/ACF composites with TNB electrolyte and their photocatalytic effect

Won Chun Oh,Ming Liang Chen 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.2

In this study, we have investigated a method for the electro-chemical preparation of TiO2/ACF composites involving the electro-plating of Ti in titanium n-butoxide (TNB) electrolyte into an activated carbon fiber matrix. The surface textural properties showed that the BET surface area and the total pore volume decrease as the distribution of TiO2 on the activated carbon fiber surfaces with electro-chemical operating time. The changes in XRD patterns showed typical anatase type on the TiO2/ACF composite prepared with activated carbon fiber matrix by the electro-plating method in the TNB solution. In SEM micrographs, the titanium complex particles are uniformly distributed on and the around the fibers. And some large clusters were found when the electro-chemical operating time increases. The results of chemical elemental analysis for the TiO2/ACF composites showed that most of the spectra for these samples gave stronger peaks for carbon and Ti metal than that of any other elements. From the results of thermal analysis, it could be considered that the amounts of the TiO2 components in the composite increase with an increase of the electro-chemical operating time. Finally, the prominent photocatalytic activity of the TiO2/ACF composites between c/co and time could be attributed to both the effects of catalytic decomposition and adsorptivity between the supported TiO2 and the porous fiber matrixes. In this study, we have investigated a method for the electro-chemical preparation of TiO2/ACF composites involving the electro-plating of Ti in titanium n-butoxide (TNB) electrolyte into an activated carbon fiber matrix. The surface textural properties showed that the BET surface area and the total pore volume decrease as the distribution of TiO2 on the activated carbon fiber surfaces with electro-chemical operating time. The changes in XRD patterns showed typical anatase type on the TiO2/ACF composite prepared with activated carbon fiber matrix by the electro-plating method in the TNB solution. In SEM micrographs, the titanium complex particles are uniformly distributed on and the around the fibers. And some large clusters were found when the electro-chemical operating time increases. The results of chemical elemental analysis for the TiO2/ACF composites showed that most of the spectra for these samples gave stronger peaks for carbon and Ti metal than that of any other elements. From the results of thermal analysis, it could be considered that the amounts of the TiO2 components in the composite increase with an increase of the electro-chemical operating time. Finally, the prominent photocatalytic activity of the TiO2/ACF composites between c/co and time could be attributed to both the effects of catalytic decomposition and adsorptivity between the supported TiO2 and the porous fiber matrixes.

Characteristics of Surface Modified Activated Carbons Prepared by Potassium Salt Sequentially After Hydrochloric Acid Treatment

Won-Chun Oh,Chong-Sung Park,Jang-Soon Bae,Young-Shin Ko 한국탄소학회 2006 Carbon Letters Vol.7 No.1

The objective of this paper is to compare the variation of surface properties by hydrochloric acid pre-treatment and of metallic potassium and their salts loading effect for activated carbon after surfaces transformation by acid. From the results of nitrogen adsorption, each isotherm shows a distinct knee band, which is closely related to the characteristic of microporous carbons with capillary condensation in micropores. In order to present the causes of the differences in surface properties and SBET after the samples were treated with hydrochloric acid, pore structure and surface morphology are investigated by adsorption analysis. X-ray diffraction (XRD) patterns indicate that activated carbons show better performance for metallic potassium and potassium salts by pre-treatment with hydrochloric acid. Scanning electron microscopy (SEM) pictures of potassium/activated carbon particles provide information about the homogeneous distribution of metal or metal complex on the surface. For the chemical composition microanalysis for potassium treatment of the activated carbon pre-treated with hydrochloric acid, samples were analyzed by energy disperse X-ray (EDX). Finally, the type and quality of oxygen groups are determined from the method proposed by Boehm. A positive influence of the acidic groups on the carbon surface by acid treatment is also demonstrated by an increase in the contents of potassium salts with increasing of acidic groups calculated from Boehm titration.

Synthesis and Characterization of Fe-containing AC/TiO₂ Composites and Their Photodegradation Effect for the Piggery Waste

Won Chun Oh 대한환경공학회 2008 Environmental Engineering Research Vol.13 No.2

In this present study, we have synthesized Fe-containing AC(activated carbon)/TiO₂ composites with titanium (VI) n-butoxide (TNB) as a titanium source to Fe treated AC through an impregnation method. The result of the textural surface properties demonstrates that there is a slight decrease in the BET surface area of composite samples with an increase of the amount of Fe treated. The surface properties of scanning electron microscope (SEM) presented a characterization of a porous texture on the Fe-containing AC/TiO₂ composites and homogenous compositions for Fe and titanium dioxide distributed on the sample surfaces. Fe compound peaks and a titanium dioxide structure were observed in the X-ray diffraction patterns for the Fe-containing AC/TiO₂ composites. The results of chemical elemental composition for the Fe-containing AC/TiO₂ composites showed that most of the spectra for these samples gave stronger peaks for C, O, treated Fe components and Ti metal than that of any other elements. From the photo degradation results for the piggery waste, the Fe-containing AC/TiO₂ composites showed an excellent degradation activity for the chemical oxygen demand (COD) due to a photocatalysis of the supported TiO₂, radical reaction by Fe species and the adsorptivity and absorptivity of porous carbon.

Silver elimination effect by sulfuric acid for Ag pre-treated activated carbon

Won-Chun Oh 한국분석과학회 2006 분석과학 Vol.19 No.2

Preparation and characterization of fullerene dimer [C<SUB>120</SUB>] by trichloroperbenzoic acid oxidation method

Won-Chun Oh,Ah-Reum Jung,Weon-Bae Ko 한국분석과학회 2007 분석과학 Vol.20 No.2

Research Articles : Hydrogen Gas Generation of Metal-Activated Carbon for Fuel Cells

( Won Chun Oh ),( Jong Yun Park ) 한국공업화학회 2007 Journal of Industrial and Engineering Chemistry Vol.13 No.4

Comparative investigation of activated porous carbons treated by silver electroplating from aqueous solution

Won-Chun Oh 한국분석과학회 2006 분석과학 Vol.19 No.3