알칼리조촉매를 사용한 Zn - Oxide 담지 촉매상에서 메탄의 Oxidative Coupling 반응특성

유의연,김상채 한국화학공학회 1990 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.28 No.5

조성과 담체 및 알칼리조촉매를 달리한 Zn-Oxide 촉매상에서 메탄의 oxidative coupling 반응에 의한 에틸렌과 에탄의 합성반응을 연구하였다. 담지촉매의 산점은 에틸렌과 에탄의 선택도를 감소시켰으며, 산점이 나타나지 않은 Zn-Oxide/α-Al₂O₃ 촉매의 선택도가 우수하였고 Zn-Oxide의 최적 담지량은 60wt%일 때이었다. Zn-Oxide/α-Al₂O₃ 촉매계에 할로겐족 원소가 함유된 알칼리금속 조촉매들을 첨가할 때의 활성순서는 NaBr>NaCl>NaI>NaF로 나타났으며, 에틸렌의 생성에 Br과 Cl 라디칼의 역할이 제시되었지만 NaF 및 알칼리금속염 (NaN0₃, Li₂CO₃, KNO₃)은 부촉매의 역할을 하였다. NaCl(30wt%)/Zn-Oxide(60wt%)/α-Al₂O₃ 촉매상에서 속도론적 고찰을 통하여, CH₃ 라디칼의 생성에 관여하는 산소종은 표면상의 이원자산소인 O^(2-)₂나 O^-₂로 제시할 수 있었고 활성화에너지는 약 39Kca1/mole 이었다. The oxidative coupling of methane to ethylene and ethane was studied over Zn-Oxide catalysts with different compositions of catalysts, different supports and promoters. The selectivity for C₂(C₂H₄+C₂H_6) decreased with an increase in the acid sites of supported catalysts. The Zn-Oxide/α-Al₂O₃ catalyst without acid sites showed that a good C₂(C₂H₄+C₂H_6) selectivity. The optimal loading of Zn-Oxide was 60 wt%. When alkali halide promoters were added to Zn-Oxide/α-Al₂O₃, the activity order was NaBr>NaCl>Nal>NaF. Br and Cl radicals might play an important role in formation of ethylene, but NaF and alkali metal salts (NaNO₃, Li₂CO₃, KNO₃) played a role of inhibitor. From kinetic studies on oxidative coupling of methane over NaCl(30wt%)/Zn-Oxide(60wt%)/α-Al₂O₃, the oxygen species responsible for formation of CH₃ radical was suggested to be diatomic oxygen (O^(2-)₂ or O^-₂) on the surface. The activation energy was ca. 39 Kcal/mole.

알칼리조촉매를 사용한 Zn - Oxide 담지 촉매상에서 메탄의 Oxidative Coupling 반응특성

유의연,김상채 한국화학공학회 1990 NICE Vol.8 No.5

폐플라스틱의 재활용에 관한 연구

유의연,김상채,선우창신,정도성 한국공업화학회 1998 응용화학 Vol.2 No.1

Photolysis behaviors of pesticides over UV irradiation, UV irradiation with pH 3.0 and UV irradiation with 3.5% salt were studied. The reactions were conducted in annular reactor equipped with a low pressure mercury multilamp (8W x 6) and initial concentration was 10ppm.

연구발표논문초록 : Ethyl Alcohol 의 탈수반응에 있어서 Alumina 촉매의 활성

유의연 한국화학공학회 1978 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.16 No.3

문화적 성향이 집단 창의성 변화에 미치는 차별적 효과

유의연,최지은 한국창의력교육학회 2022 창의력교육연구 Vol.22 No.3

Recently, Asian countries, including Korea and China, are rapidly changing from a traditional collectivist culture to an individualistic culture. Therefore, it is necessary to investigate how individualism as an individual traits affects group creativity, which essentially requires social interaction. Under the background, we divided the cultural orientations of Chinese university students into the four types of Triandis (1995): vertical individualism, horizontal individualism, vertical collectivism, and horizontal collectivism. And then we constructed 4 homogeneous groups according to each types, and their group creativity was tested three times over an 8-week period. The results were first, in the last measurement, the groups with the highest group creativity were the horizontal collectivist team and the vertical individualistic team. Although the horizontal collectivist team had the lowest score among the four teams at the beginning, it continued to show a steep rise over time, showing the highest score in the last. The vertical individualist team started with a high score from the beginning and maintained a consistently high level. The vertical collectivist team seemed to maintain a high level of group creativity from the beginning to the middle, but showed a sharp decrease at the end. The horizontal individualism team showed low group creativity from the beginning and tended to keep it at a low level. This tendency was also supported by peer ratings and expert ratings. In the subsequent discussion, the causes of this tendency were analyzed, implications and limitations, and suggestions for future research were discussed. 최근 중국은 전통적인 집단주의 문화에서 개인주의 문화로 빠르게 변화되고 있다. 이에 개인의 성향으로서의 개인주의, 집단주의가 본질적으로 사회적 상호작용을 필요로 하는 집단 창의성에 어떤 영향을 미치는지 알아볼 필요가 있다. 이러한 배경 하에 본 연구는 중국 대학생의 문화적 성향을 Triandis(1995)의 4유형으로 구분하고, 각 유형에 따라 동질적인 팀을 구성한 후, 12주간의 집단 활동을 거치는 동안 총 3차례에 걸쳐 집단 창의성의 변화 양상을 살펴보았다. 연구결과 첫째, 마지막 측정에서 집단 창의성이 가장 높은 집단은 수평적 집단주의팀과 수직적 개인주의팀이었다. 수평적 집단주의팀은 초반에 가장 낮은 점수를 보였지만, 시간이 흐르면서 지속적으로 가파른 상승폭을 보여 마지막 측정에서 가장 높은 점수를 나타냈다. 수직적 개인주의팀은 초반부터 높은 점수로 출발해서 지속적으로 높은 수준을 유지했다. 수직적 집단주의 팀은 초, 중반까지 높은 집단 창의성 수준이 유지되는 듯했으나 마지막에 급격하게 감소하는 양상을 보였다. 수평적 개인주의팀은 초반부터 낮은 집단 창의성을 보이며 계속 낮은 수준을 유지하는 경향을 보였다. 이러한 경향성은 동료평정과 전문가 평정에서도 지지되었다. 이후 논의에서 이러한 경향성이 나타난 원인을 분석하고, 시사점과 한계점, 향후 연구를 위한 제언을 하였다.

촉매를 이용한 폐고분자물질의 자원화 (Ⅱ)

유의연,서곤,최병렬,장문수,강웅일 한국공업화학회 1998 응용화학 Vol.2 No.1

Low molecular weight polyethylene, a by-product of high density polyethylene process, was used to produce oxidized polyethylene waxes. The effects of some key parameters such as temperature and time for oxidation, air or oxygen flow rates into the reactor on the acid number, and component distribution have been investigated. The instruments used to analyze properties of oxidized polyethylene waxes were the GPC, DSC, NMR, FT-lR, and SEM. The results indicated that the acid number increased in value as the temperature was raised up to 150℃. The change in acid number was found to be properional to air flow rates. It was also discovered that during the oxidation process the molecular weights of the product decreased, but their distribution became broader at higher acid numbers.

개시제를 이용한 폴리에틸렌 왁스상에 MAH그라프팅 반응

강웅일,선우창신,유의연 全南大學校 觸媒硏究所 1998 觸媒硏究 論文集 Vol.20 No.-

Polyethylene wax was grafted with maleic anhydride using DCPO, DTBP, BPO, AIBN as an initiators and xylene as a solvent, The effect of reaction parameters such as MAH and initiator concentration, reaction temperature on percent grafting were studied. The maximum MAH extent of grafting achieved was 4.5%. The occurrence of a grafting reaction was analyzed by FT-IR spectrum of the polymeric reaction product of strong carbonyl streching absorbtions at ?? band. The efficiency of the radical initiators in reaction of polyethylene was with maleic anhydride was in the following order : DCPO ≒ DTBP〉BPO, ≒ AIBN

Ni/Ti0₂ 촉매상에서 CO₂ 개질 반응에 있어서 조촉매 및 Ni 담지량의 영향

서호준,유의연 全南大學校 觸媒硏究所 1996 觸媒硏究 論文集 Vol.18 No.-

The effect of Ni loading andition of promoters such as KCI, NaCl, CaO and MgO was studied on the CO₂reforming over Ni/TiO₂catalysts in a fixed bed flow reactor at atmospheric pressure. 10wt% Ni loaded catalyst showed optimum activity. The effect of promoters on the catalytic activity was Ca>Mg>K>Na in order. Adding promoter could be suggested that the reverse Boudouard reaction occur.

열분해반응을 통한 폴리에틸렌-폴리프로필렌 혼합물의 오일회수 특성

정도성,김상채,유의연 全南大學校 觸媒硏究所 1998 觸媒硏究 論文集 Vol.20 No.-

The thermal degradation of polyethylene, polypropylene alone an their mixture into oil and gas products has been carried out at different reaction conditions. The effect of various parameters such as temperatures, space velocity, mixing ratio on the yield and composition of the oil recovery for these polymers at different reaction temperature. In polyethylene-polypropylene mixtures, the more polypropylene is added, the more rate of degradation of PE and conversion of PE/PP mixture increase at a lower temperature than that of PE alone. It is proposed that this enhancement is due to the free radical from polypropylene, in which can form free radical from polyethylene a lower temperature.

이산화탄소에 의한 메탄 개질반응에서 니켈계 담지촉매의 탄소 침적에 관한 연구

조영복,선우창신,김상채,유의연 全南大學校 觸媒硏究所 1998 觸媒硏究 論文集 Vol.20 No.-

The reforming of methane by carbon dioxide is studied over nickel based catalysts, which compared the influence of the support in catalyst activity and carbon deposition. The experiments were carried out at atmospheric pressure using a fixed bad flow reactor. The catalytic activity and carbon deposition is influenced by support. The Ni/α-Al₂O₃showed high methane conversion. The Ni/La₂O₃ showed high methane conversion, but the reactor was plugged in 15 h. The carbon deposition was observed in all nickel based catalysts. Compared to Ni/α-Al₂O₃, Ni/La₂O₃, catalyst showed higher whisker carbon formation. Whisker carbon was not observed in the Ni/MnO₂. The carbon deposition of the nickel based catalysts increased in the order MnO₂〈SiO₂〈α-Al₂O₃〈TiO₂〈La₂O₃. The carbon deposition on the catalysts was affected by reaction conditions such as temperature, molar ratio(CO₂/CH₄).