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Literature Report. Feng Jiang 2013.5.10. high-energy costs. Dehydrogenation. coke formation. ODH with O 2. Low selectivity. ODH with CO 2. soft oxidant. CO 2. Carbon dioxide utilization as a soft oxidant and promoter in catalysis.
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Literature Report FengJiang 2013.5.10
high-energy costs Dehydrogenation coke formation ODH with O2 Low selectivity ODH with CO2 soft oxidant CO2
Carbon dioxide utilization as a soft oxidant and promoter in catalysis Mohd Bismillah Ansari and Sang-Eon Park* Energy Environ. Sci., 2012, 5, 9419-9437
Role of CO2 form CO and oxygen species and change the dehydrogenation pathway in an oxidative manner • alleviate the chemical equilibrium in ODH • H2 +CO2 → CO + H2O • suppress coking via a decoking reaction • C+CO2→ 2CO
acid–base properties: Without CO2 With CO2 4
surface/lattice oxygen species: R–CH2CH3 +MOx → R–CH=CH2 +H2O+MOx-1 MOx-1+CO2 → MOx+ CO CO2 maintains the lattice oxygen of the catalyst
18O isotope experiment M16Ox+C18O2→M18O16Ox-1+ C18O16O M16Ox+C18O2→M18O216Ox-2+ C16O2 Nihao MS record: C18O2,m/z 48; C18O16O,m/z 46; C16O2, m/z 44 MOx-1 +CO2 → MOx+ CO really exists
Redox mechanism √ Chromium, and Vanadium oxide-based catalysts × Gallium, Indium oxide-based catalysts
(1) • (2) • (3) • (4) B.J. Xu, B. Zheng, W.M. Hua, Y.H. Yue, Z. Gao, J. Catal. 239 (2006) 470-477.
(5) With CO2 • (6) • (6)>>(5) B.J. Xu, B. Zheng, W.M. Hua, Y.H. Yue, Z. Gao, J. Catal. 239 (2006) 470-477.