TY - JOUR
T1 - Reduction Kinetics of La Modified NiO/La-gamma Al2O3 Oxygen Carrier for Chemical-Looping Combustion
AU - Hossain, Mohammad Mozahar
AU - Quddus, Mohammad Rezwanul
AU - de Lasa, HI
PY - 2010
Y1 - 2010
N2 - La modified Ni/La-gamma Al2O3 oxygen carrier reduction kinetics is investigated using temperature programmed reduction (TPR) and a parameter nonlinear regression analysis. TPR profile study and XRD analysis of the completely oxidized samples show that NiO is the prevalent phase of the oxygen carrier. Hydrogen pulse chemisorption demonstrates that the nickel crystallite sizes remain unchanged over repeated reduction/oxidation cycles. A nucleation and nuclei growth model and an unreacted shrinking core model are developed based on the oxygen carrier characterization. Model discrimination is conducted based on SSQ, goodness of fittings, and minimum cross-correlation coefficients. On the basis of these statistical indicators, it is established that the random nucleation model describes the reduction of the oxygen carrier adequately. The estimated value of the activation energy for the La modified Ni/La-gamma Al2O3 sample is found to be 73.4 +/- 2.6 kJ/mol, with this being significantly low
AB - La modified Ni/La-gamma Al2O3 oxygen carrier reduction kinetics is investigated using temperature programmed reduction (TPR) and a parameter nonlinear regression analysis. TPR profile study and XRD analysis of the completely oxidized samples show that NiO is the prevalent phase of the oxygen carrier. Hydrogen pulse chemisorption demonstrates that the nickel crystallite sizes remain unchanged over repeated reduction/oxidation cycles. A nucleation and nuclei growth model and an unreacted shrinking core model are developed based on the oxygen carrier characterization. Model discrimination is conducted based on SSQ, goodness of fittings, and minimum cross-correlation coefficients. On the basis of these statistical indicators, it is established that the random nucleation model describes the reduction of the oxygen carrier adequately. The estimated value of the activation energy for the La modified Ni/La-gamma Al2O3 sample is found to be 73.4 +/- 2.6 kJ/mol, with this being significantly low
M3 - Article
SN - 0888-5885
JO - Industrial and Engineering Chemistry Research
JF - Industrial and Engineering Chemistry Research
ER -