CFC-113a의 수소화 반응에서 Pd/Al2O3 촉매의 불소화가 촉매성능에 미치는 영향을 고찰하였다. 불소화시킨 F-Pd/Al2O3촉매의 CFC-113a 수소화 반응 전화율이 Pd/Al2O3의 전화율보다는 높게 나타났다. F-Pd/Al2O3가 Pd/Al2O3에 비해 반응 전화율이 뛰어난 이유는 XRD와 TEM으로 확인한 결과, 불소화 처리는 반응 중의 팔라듐의 응집을 방지할 수 있었으며, 팔라듐은 불소화에 의해 Pd metal과 Pd-F 결합을 형성하는 것을 XRD와 EXAFS를 통하여 관찰하였다. Pd-F는 담체와의 강한 interaction에 의해 팔라듐의 sintering을 방지하는 것으로 생각된다. 또한 담체로 사용된 γ- Al2O3는 불소화 후에 AlF3로 바뀌고 비표면적이 감소하는 것을 확인하였다.
The effect of fluorination over Pd/Al2O3 catalyst have been investigated in the hydrogenation of CFC-113a. Fluorinated Pd/Al2O3(F-Pd/Al2O3) catalysts showed higher conversion of CFC-113a than Pd/Al2O3 catalysts. Fluorinated treatment, from the characterization of used catalysts by XRD, TEM and EXAFS, prevented sintering of palladium particles during reaction and some parts of palladium formed a matallic state palladium as well as fluorinated Pd(Pd-F) upon fluorination. The Pd-F bonding suggested strong interaction with support which can decrease the sintering of Pd particles during reaction. Simultaneously, it was also confirmed that γ-Al2O3 phase changed to A1F3 and the surface area decreased after fluorination process.
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