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The effects of various anions containing copper based catalysts were studied in regard to the preparation of dimethyl carbonate (DMC) through oxidative carbonylation of methanol under a liquid phase system. A copper compound providing the strong withdrawing power of halides as anion yielded excellent results with respect to the conversion of methanol and selectivity to DMC. However, copper homogenous catalysts suffer from separation of the catalyst after reaction. Thus, the development of a new reaction system using various supports including Y-zeolite was attempted. The conversion of methanol and selectivity to DMC were affected by the properties of the supports. In particular, Y-zeolite showed the best yield among various supports. The influence of various promoters was examined with the aim of increasing the yield of DMC from methanol. The yield of DMC was increased with the addition of alkali metal in the order Li + + + , but with selectivity in the order of Li + > Na + > K + , respectively. Various analyses were conducted in order to elucidate these results. From a XRD analysis, the existence of crystal forms of copper chloride hydroxide of Cu/Na/Y-zeolite (dry) was observed. We confirmed the presence of peaks of CuO in Cu/Na/Y-zeolite (550 °C). The CO-TPD analysis revealed that CO desorption is an important step to determine the formation of DMC. The addition of NaOH as a co-catalyst resulted in a lower desorption temperature of carbon monoxide in Cu catalyst. Also, XPS analysis results showed that Cu + on the calcined Cu/Na/Y-zeolite catalyst was formed by the reduction of Cu 2+ . XANES results provided the difference of reactivity according to the state of the copper catalyst. Activity of this reaction in terms of DMC yields, obtained in the order of CuCl 2 > Cu/Na/Y-zeolite (dry) > Cu/Na/Y-zeolite (550 °C) > Cu(OH) 2 was in accordance with the maximum peak of the low photon energy position.

회분식 고압반응기에서 메탄올 산화 카르보닐화 방법에 의한 디메틸 카보네이트 제조에 대하여 연구하였다. 다양한 금속의 영향과 구리촉매에 결합된 음이온 및 반응온도, 일산화탄소, 산소의 반응물 몰비, 구리촉매 함유량 등 여러 반응조건들을 검토하였다. 특히 CuCl2·2H2O 촉매가 1.0 g, 150 ˚C, MeOH/CO/O2=0.2/0.215/0.05(molar ratio) 반응조건에서 메탄올 전환율 65.2%, 선택도 96.6%로 좋은 활성을 보였다. CuCl2는 반응기의 부식을 일으킨다. 이러한 문제점을 개선하기 위하여 DMC 제조에서 담체를 이용한 새로운 촉매시스템을 검토하였다. 여러 종류의 담체중 산성이 큰 제오라이트 Y를 담체로 사용한 경우 가장 활성이 우수하였다. ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometer)를 이용해 반응기에 용출된 Fe 양을 비교하였을 때, 제오라이트를 담체로 사용하여 제조된 구리촉매는 CuCl2-2H(2)O 촉매를 직접 사용한 경우에 비해 반응기로 용출되는 철의 양은 5% 이하이었다.