KINETICS OF OXIDATION OF A REDUCED FORM OF THE Cu-BASED OXYGEN-CARRIER FOR USE IN CHEMICAL-LOOPING COMBUSTION
A co-precipitated mixture of CuO and Al2O3 is a good oxygen-carrier for chemical-looping combustion. The kinetics of regeneration of this reduced oxygen-carrier (355 – 500 μm) were measured from 300 to 750℃ when reacting it with O2. Care was taken to ensure these measurements were not affected by interphase mass transfer. Efforts were also made to minimise sampling problems by using a rapid-response mass spectrometer for reactions lasting for 45 s or less; otherwise, a paramagnetic analyser for O2 was used, since the mass spectrometer drifted with time. The order of reaction with respect to O2 was found to be ~ unity at 300 to 750℃. Below 600℃, the reduced oxygen-carrier was incompletely oxidised to a mixture of Cu2O and Al2O3. Above 600℃, regeneration was completely to CuO and Al2O3 and was controlled to a considerable extent by external mass transfer. At these higher temperatures, regeneration involved a shrinking core mechanism and the two consecutive steps: 2Cu + 1/2O2 → Cu2O, (1) Cu2O + 1/2O2 → 2CuO. (2) The activation energies and pre-exponential factors for both reactions were measured from initial rates. The kinetics in the first cycle of operations were found to be similar to those in the subsequent cycles.
chemical-looping combustion ozygen-carrier kinetics fluidised bed
S.Y.Chuang J.S.Dennis A.N.Hayhurst S.A.Scott
Department of Chemical Engineering and Biotechnology, University of Cambridge Pembroke Street,Cambri University of Cambridge, Department of Engineering, Trumpington Street, Cambridge, CB2 1PZ, UK
国际会议
第20届国际流化床燃烧会议(20th International Conference on Fluidized Bed Combustion)
西安
英文
512-518
2009-05-18（万方平台首次上网日期，不代表论文的发表时间）