고정화된 TiO_2 광촉매를 이용한 암모니아 제거반응

박용완,김영철,신재순,박남국 全南大學校 觸媒硏究所 2002 觸媒硏究 論文集 Vol.23 No.-

Physical properties of TiO_2 photocatalyst prepared by sol-gel process and photodegradation behaviors of NH_3 gas over TiO_2 immobilized on glass bead were studied. The surface area and average pore size of photocatalyst C were 148.3m^2/g and 138.3A˚, respectively. The XRD patterns of TiO_2 photocatalyst prepared by sol-gel method which were calcinated 400℃ showed that the catalyst had almost an anatase structure. Optimum thickness of TiO_2 layer was 5㎛ and immobilization frequence was four times. TiO_2 glass bead immobilized by powder coating method was a little better effective than it prepared by sol-gel method, but restriction of supports and economy were less than it immobilized by sol-gel method. The highest treatment efficiency was obtained when the wavelenght of UV lamp was 254nm. The photodegradation efficiency compared with some commercial TiO_2 photocatalyts, TiO_2 photocatalyst prepared by sol-gel method in laboratory is better.

접촉수소화에 의한 이산화탄소의 화학적 고정화

박종래,박남국,서성규 여수대학교 1998 論文集 Vol.12 No.2

The chemical fixation of carbon dioxide by hydrogenation over supported Ni catalysts was studied using an atmospheric pressure flow reactor. The mole ratio of carbon dioxide and hydrogen as a reactants was 1:4. The effect of reaction and reduction temperature, loading amount, and support type was examined to the catalytic activity. Also, the physico-chemical properties of catalyst were investigated by XRD(X-ray diffractometer), H₂-TPR(temperature programmed reduction) and NH₃-TPD(temperature programmed desorption). The conversion of CO₂and the selectivity of CH₄were increased with increasing of the reaction and reduction temperature, loading amount, and decreasing of the support acidity.

팔라듐 담지 촉매에 의한 메탄의 연소반응

박남국,신재순,김덕중,최영현,김영철 全南大學校 觸媒硏究所 1997 觸媒硏究 論文集 Vol.19 No.-

Catalytic oxidation of methane was studied in a fixed bed flow reactor. Supported Pd and La promoted Pd catalysts were prepared by incipient wetness impregnation method. Up to 0.5wt.% of Pd, the catalytic activity was increased with Pd loading. However, the activity did not change above that loading. 0.1wt.% La added Pd catalysts showed increased catalytic activities due to increased methane and oxygen adsorption. La addition proved to increase the dispersion, thus increases thermal stability of the catalysts. However, when the loading of La exceeds 1.0wt.%. methane oxidation activity was decreased. presumably due to the pore and Pd blocking by added La.

PS와 PAMS의 오존에 의한 분해 반응

김아영,박남국,신재순,김영철 全南大學校 觸媒硏究所 2003 觸媒硏究 論文集 Vol.24 No.-

An investigation study showed the enhancement effect of ozone on the degradation of polystyrene (PS) and poly(α-methylstyrene) (PAMS). At various temperatures and concentrations of ozone, experiments were conducted, and the samples were taken and analysis by GPC (Gel permeation chromatography). We observed the degradation of PS and PAMS were enhanced at higher reaction temperatures, which cause chain scission vigorously, and at higher concentrations of ozone. For confirmation of ozone's nature as a strong oxidizer, the activation energy derived from the degradation by ozone additon was compared with those from thermal and catalytic degradation, and turned into much lower than the other cases.

연질폴리우레탄폼의 물리적 성질 및 흡음율에 관한 연구

정종원,박남국,박선정,박종래,김영철 全南大學校 觸媒硏究所 1997 觸媒硏究 論文集 Vol.19 No.-

The effects of polyols, isocyanates. surfactants and water on the physical properties of the polyurethane foam were investigated. The resin used in this study was prepared from a variety of polyol mixtures by adding catalyst, surfactant and cross-linker. The polyurethane was foamed from the resin by adding an equivalent amount of isocyanate and was used in property measurements. The physical properties were more affected by the type of isocyanates and the amount of water than the sound absorption coefficient. The sound absorption coefficient of the polyurethane foam was superior for the polyol mixture of KE-810(40%)FA-733(40%)/FA-703(20%). The sound absorption coefficient was increased with the amount of surfactant L-5309 up to 3000Hz, but was decreased above that frequency.

페롭스카이트 촉매를 이용한 메탄의 부분산화반응

이승재,김영철,박남국,신재순 전남대학교 촉매연구소 2001 觸媒硏究 論文集 Vol.22 No.-

Partial oxidation of methane to synthesis gas is the most profitable among the reforming reactions. It can be used in methanol and DME synthesis as well as in the Fischer- Tropsch processecs. Perovskite catalysts were studied in partial oxidation of methane to syngas production using a fixed bed flow reactor under an atmospheric pressure. La was taken as a basic material in A site. TPR and XRD analysis were compared in the view of the catalytic activity. The active phase seems to be the reduced metal. The order of activity was observed in the flollowing order: Ni > Co > Fe. The synergitic effect of substitution in B site was showen when x = 0.3 in the reduced LaNil-xCoxO3 catalysts.

백금과 세리아를 담지한 촉매의 포름알데히드 산화반응에 관한 연구

김영철,김재승,박남국,김재관,신재순 全南大學校 觸媒硏究所 1996 觸媒硏究 論文集 Vol.18 No.-

Total oxidation of formaldehyde was studied using platinum and platinum-ceria catalysts supported on γ- alumina. Catalysts were prepared by coimpregnation with γ- Al₂O₃, Platinum and ceria loading were controlled as 0.02∼0.04wt% and 0.3∼7.6wt%, respectively. The characterization of the catalysts were investigated by catalytic activity, O₂-TPD and H₂-TPR. The order of catalytic activities in view of formaldehyde conversion was as follows ; Pt+Ce(0.3%)/Al₂O₃>Pt+Ce(0.8%)/Al₂O₃>Pt+Ce(5%)/Al₂O₃>Pt+Ce(7.6%)/Al₂O₃>Pt/Al₂O₃. Small amount of added ceria enhanced the catalytic activity. However, as the amount of ceria increased the activity was decreased. Optimum loading of ceria seems to be 0.3∼0.8w%.

폴리에틸렌과 폴리프로필렌의 촉매분해

김태환,이재기,김영철,박남국,신재순 전남대학교 촉매연구소 2001 觸媒硏究 論文集 Vol.22 No.-

Converting of wasted plastics into oil can be used as a new energy source. It has advantages of reducing the environmental problems and produces additional economic values. In this study, polyethylene and polypropylene were catalytically degraded by JSA-1(Si/Al=6.7), JSA-2 (Si/Al=2.57), HZSM-5 (Si/Al=30.2) and MCM-48(Si/Al=100/0) catalysts to investigate the optimum degradation conditions. The order in liquid product yield was JSA-2 > JSA-1 > HZSM-5. Liquid product yield was increased with the catalyst loading, but the carbon number distribution of the liquid product was widely spreaded. When the HZSM-5 was phosphated to regulate the acidity, the liquid product yield was in the order of P (2 wt %) HZSM-5 > P (1 wt %) HZSM-5 > HZSM-5 > P (3 wt %) HZSM-5. The optimum acidic amount and strength of the phosphated HZSM-5 was achieved when 2 wt % P was loaded. It was confirmed by the ammonia TPD. HMCM-48 with acid sites was not blocked by carbon deposition because of the large pore size. So, it seems to promote the catalytic activity of the plastic degradation.

페롭스카이트 촉매를 이용한 메탄의 포름알데히드로의 부분산화반응

김영준,강춘형,김영철,박남국,신재순 全南大學校 觸媒硏究所 2002 觸媒硏究 論文集 Vol.23 No.-

The direct conversion of methane or natural gas into useful hydrocarbon and oxygenated products has been the subject of extensive research during the past decade. Partial oxidation of methane to formaldehyde was studied in a fixed-bed continuous flow reactor at the temperature range of 473-973 K using perovskite catalyst. La was taken as a basic material in A site. Ni, Co and Fe have been studied to test the catalytic activity and HCHO selectivity in partial oxidation of methane. Then La in A site was replaced by Ce and Co to study the activity change. TPR and XRD analysis were compared in view of the catalytic activity. The order of activity was observed in the flollowing order: LaNiO_3 > LaCoO_3 > LaFeO_3. The highest HCHO selectivity was 16.4% on reduced LaNi_0.8Co_0.2NiO_3 at 450℃.

은 첨가 복합산화물 촉매에 의한 벤젠의 산화제거반응

김성희,김영철,김덕중,박남국 全南大學校 觸媒硏究所 1998 觸媒硏究 論文集 Vol.20 No.-

Complex metal oxide catalysts were tested for the removal of benzene from 150℃ to 300℃ in an atmospheric fixed bed flow reactor. Supported Mn and Ag increased catalytic activity. Particularly Mn had an effect on catalytic activity when it was a little an caused decreasing of catalytic activity when it was much because metallic Ag was decreased. La didn't have an effect on catalytic activity but stability. Supported Ag plated an important role in catalytic activity when it was metallic Ag which was present at low calcination temperature(400℃) but caused decreasing of catalytic activity at high calcination temperature(800℃) because it was transformed into Ag₂MnO₄.