Processes like Fisher-Tropsch synthesis that yield a very large spectrum of products present challenges for modeling approaches due to the large networks that are involved. The number of species involved in such a network increases exponentially if the model concerns isotopic exchange experiments due to the distribution of the labeled atom into the products. Special tools such as a code for computer to generate a reaction network have been developed to deal with the complexity of Steady-State Isotopic Kinetic Analysis (SSITKA) experiments. This approach makes it easier to model both steady-state and SSITKA experiments based on a microkinetic reaction mechanism. The methodology is applied to (CO)-C-12 -> (CO)-C-13 SSITKA experiments for Fisher-Tropsch synthesis over a 13 wt.% Co/Al2O3 catalyst oriented towards two different Co phase structures, face-centered cubic and hexagonal close-packed, by different pre-treatments. (C) 2016 Elsevier B.V. All rights reserved.