| Abstract
| - A generalized kinetic model for fly ash native carbonoxidation is developed. It is shown that the conversion offly ash native carbon to CO2 is the result of twosimultaneous processes taking place on fly ash surface: the first process (rate constant k2) is the direct oxygen transferfrom a metal oxide site to a vacant carbon active siteleading to immediate carbon gasification; the second oneis dissociative oxygen chemisorption (k1) followed byC(O) complex intermediate uncatalyzed gasification (k3).The model is validated using the kinetic data from modelsystems and those reported in Part 1 for four different flyashes. The rate constants, k1, k2, and k3, together withactivation and thermodynamic parameters are calculated.For each fly ash, the rate determining step is the complexintermediate oxidation. The nature of the interaction betweennative carbon and the fly ash surface is the key factorfor C and C(O) complex formation and gasification.
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