Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.13/39579
- Conversion of CHF₃ to CH₂=CF₂ via reaction with CH₄ and CaBr₂
Kennedy, Eric M.;
Mackie, John C.;
Dlugogorski, Bogdan Z.
- The University of Newcastle. Faculty of Engineering & Built Environment, School of Engineering
- Reaction of CHF₃ and CH₄ over CaBr₂ was investigated at 400-900 degrees C as a potential route for transforming the highly potent greenhouse gas, CHF₃, into the valuable product CH₂=CF₂. The homogeneous reaction of CHF₃ with CH₄ was also studied to assist in understanding the chemistries involved. Compared to the gas phase reaction, the addition of CaBr₂ as a reactant increases the conversion of CHF₃ and CH₄ significantly at low temperatures while to a lesser extent at higher temperatures. In the absence of CaBr₂, besides the target product, CH₂=CF₂, a large amount Of C₂F₄ forms. On addition of CaBr₂, the rate of formation Of C₂F₄ drops dramatically to near zero, while the rate of formation of CH₂=CF₂ increases considerably at temperatures below 880 degrees C. Experimental and theoretical studies suggest that CHF₃ strongly interacts with CaBr₂, resulting in the fluorination of CaBr₂ to CaF₂, the release of active Br species results in the selective formation of CBrF₃. The subsequent reactions involving Br, methane, and CBrF₃ play a major role inthe observed enhanced yield of CH₂=CF₂.
- Environmental Science & Technology Vol. 42, Issue 15, p. 5795-5799
- Publisher Link
- American Chemical Society
- Resource Type
- journal article