Recently,
methanol has gained increasing attention thanks to the
variety of feedstocks suitable for its production and its low environmental
impact granting the molecule a key role in future economic roadmaps
as in Olah’s development model. Nowadays, fossil sources are
not the exclusive sources to produce syngas: biogas is a promising
alternative, leading to less severe operating conditions and smaller
plant scales. The most widespread kinetic models for methanol synthesis,
namely, the Graaf and the Vanden Bussche–Froment models, will
be proven not to be fully adequate in characterizing these conditions.
A robust refit is shown to outperform predictions from conventional
models and follow recent trends in process operations. The refitted
Graaf model is more flexible on the operating conditions and feed
compositions, removing also some infeasible discontinuities present
in conventional models. The final result is a more generalized and
accurate Graaf’s model for methanol synthesis on CZA catalysts.