Cu/Ni 조성비를 달리하여 제조한 Cu-Ni/SiO₂ 촉매를 사용하여 메탄올 분해반응을 수행하였고, 니켈 단독촉매와 비교하여 구리의 역할을 알아보았다. Cu-Ni/ SiO₂ 촉매의 구리 표면조성은 니켈 표면조성보다 월등히 높지만 메탄올 분해반응에 대한 활성화 에너지, 선택도 및 활성이 니켈 단독촉매의 그것들과 유사하였기 때문에 메탄올 분해는 주로 니켈 활성점에서 일어난다고 판단된다. 구리의 존재는 인접한 니켈 활성점 쌍을 감소시키므로서 메탄올 분해의 TOF(turnover fre- quency)를 감소시키고 메탄의 생성을 억제시키는 작용을 하였다. Cu/Ni비가 증가함에 따라 메탄의 생성은 점차 저해되었으나, 활성화 에너지와 TOF는 일정한 경향이 없었다. 반응차수는 CU/Ni비해 관계없이 거의 일정하였고, 또한 니켈 단독촉매와는 달리 메탄올 분압에 관계없이 일정하였으며, 이것은 구리의 영향 때문으로 생각한다.

Decomposition of methanol over Cu-Ni/SiO₂ catalysts which were prepared with various Cu/Ni ratios was carried out and the roles of copper were in- vestigated by comparing the reaction results with those obtained from a nickel -only catalyst. Although the surface composition of copper was much higher than that of nickel, the overall catalytic characteristics such as the activation energy, selectivity and activity were similar to those of the nickel-only cata- lyst. Thus it is concluded that the decomposition of methanol takes place mainly on the nickel sites. Incorporation of copper reduces the number of adjacent nickel-site pairs, resulting in decrease of the TOF(turnover frequen- cy) of methanol decomposition and inhibition of the methane formation. As the Cu/Ni ratio increased, the formation of methane became more inhibited while no obvious trend was observed for the activation energy and the TOF. The reaction order was almost independent of the Cu/Ni ratio and also remained constant with the partial pressure of methanol, contrary to the case for the nickel-only catalyst; this is considered to be another effect of copper.

Copper-Nickel Decomposition Methanol Silica-supported

서곤, 촉매, 4(2), 125 (1988)
하백현, 촉매, 7(1), 10 (1991)
Miyazaki E, Yasumori I, Bull. Chem. Soc. Jpn., 40, 2012 (1967) 
Madhusudhan RV, Shankar V, J. Chem. Technol. Biotechnol., 42, 183 (1988)
Cant NW, Tonner SP, Trimm DL, Wainwright MS, J. Catal., 91, 197 (1985) 
Imai T, Shokubai, 28, 195 (1986)
Idem RO, Bakhshi NN, Ind. Eng. Chem. Res., 33(9), 2047 (1994) 
Idem RO, Bakhshi NN, Ind. Eng. Chem. Res., 33(9), 2056 (1994) 
Kiyoura T, Jimbo T, Kogure Y, Kanaya K, Eur. Patent, 409517 (1990)
Yasumori I, Nakamura T, Miyazaki E, Bull. Chem. Soc. Jpn., 40, 1372 (1967) 
Gasser RPH, Roberts K, Stevens AJ, J. Catal., 37, 179 (1975) 
Gates SW, Russel JN, Yates JT, J. Catal., 92, 25 (1985) 
Rubloff GW, Demuth JE, J. Vac. Sci. Technol., 14, 419 (1977) 
Demuth JE, Ibach H, Chem. Phys. Lett., 60, 395 (1979) 
Richter LJ, Ho W, J. Vac. Sci. Technol. A, 3, 1549 (1985) 
Richter LJ, Ho W, J. Chem. Phys., 83, 2569 (1985) 
Bare SR, Stroscio JA, Ho W, Surf. Sci., 150, 399 (1985) 
Steinbach F, Krall R, Cai JX, Kiss J, Proceed. 8th Int. Congr. Catal., DECHEMA, Frankfurt, 3, 359 (1984)
Yoon KJ, Jeong KS, Yie JE, HWAHAK KONGHAK, 31(5), 569 (1993)
Benson JE, Boudart M, J. Catal., 4, 704 (1965) 
Pannell RB, Chung KS, Bartholomew CH, J. Catal., 46, 340 (1977) 
Parris GE, Klier K, J. Catal., 97, 374 (1986) 
Vannice MA, J. Catal., 37, 449 (1975) 
Sinfelt JH, Carter JL, Yates DJC, J. Catal., 24, 283 (1972) 
Kaminsky M, Yoon KJ, Geoffroy GL, Vannice MA, J. Catal., 91, 338 (1985) 
JDPDS: "Powder Diffraction File Search Mannual Hanawalt Method," International Center for Diffraction Data (1986)