Mass-transfer parameters in gas-solid reactive media to identify permeability of IMPEX

Lu et al.'s modeling of gas-solid reaction demonstrated the significant inf luence of mass transfer on the global transformation of consolidated porous reactive media with reactive gas at low pressure and low permeability: The ir model coupled mass transfer with chemical kinetics at the grain level an d heal transfer with mass transfer at the pellet level. The comparison betw een simulation results and recent experiments demonstrated that the value o f the material permeability varies during the reaction process This study p resents the permeability decrease during the synthesis process. A correlati on representing the nonlinear evolution of permeability was identified for different reactive materials used for experiments. These mechanisms salt sa tisfactorily explain both the experimental measurements of global advanceme nt and local temperature profiles.