Issue
HWAHAK KONGHAK,
Vol.38, No.5, 585-590, 2000
알칼리 및 산으로 처리한 활성탄에 담지시킨 팔라듐 촉매상에서 CFC-12(CCl2F2)의 수소화 분해반응
Catalytic Hydrogenolysis of CFC-12(CCl2F2) over Pd Catalyst Supported on Activated Carbon Treated with Alkali and Acids
알칼리 및 산 혹은 두 가지 산으로 연속하여 전처리한 활성탄에 담지시킨 팔라듐 촉매(Pd/C)상에서 CFC-12(CCl2F2)의 수소화 분해반응을 수행하였다. 제조한 Pd/C촉매의 특성은 원소분석, XRD, TEM, 질소 물리흡착 및 수소 화학흡착 실험을 통하여 조사하였다. 부반응을 촉진시킬 것으로 생각되는 활성탄에 함유된 미량의 금속성분은 NaOH-HCl, HCl-HF, HF-HCl 처리에 의해 상당량 제거되었음을 확인할 수 있었다. 이렇게 전처리한 활성탄을 사용하여 제조한 촉매들은 전처리하지 않은 활성탄을 사용한 촉매에 비해 뛰어난 수소화 분해반응 활성과 HFC-32(CH2F2)의 생성반응에 대해 높은 선택도를 보였다. 또한 특성분석결과 Pd의 분산도가 크게 향상되었고, 촉매의 소결(sintering) 현상이 현저히 억제되었음을 확인할 수 있었다.
Catalytic hydrogenolysis reaction of CFC-12(CCl2F2) was investigated over Pd catalysts supported on the activated carbons which were pretreated with alkali-acid and/or acid-acid in series. The Pd/C catalysts were characterized by ICP, XRD, TEM, N2 physisorption, and H2 chemisorption. Minor metal components known as the side reaction catalyst in CFC-12 catalytic hydrogenolysis in the activated carbon were removed by consecutive treatment with NaOH-HCl and/or HCl-HF, HF-HCl. The pretreated Pd/C catalysts showed higher hydrogenolysis activity and selectivity to HFC-32(CH2F2) than the corresponding untreated ones. It was found that the dispersions of the pretreated catalysts were improved and the sintering phenomena were significantly restricted.
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