Impact of Non-Ideality on Stability and Performance in Benzaldehyde Production

Exothermic reactive processes pose significant safety risks due to the possibility of thermal runaway. Reliable tools for the design, control, and optimization of such systems are therefore essential. Stability analysis provides a powerful framework, but its effectiveness depends on an adequate representation of reactor hydrodynamics. Following the pioneering work of Varma, Morbidelli, and Wu, tubular reactors have mainly been analyzed using ideal plug flow reactor (PFR) models, which may lead to a partial assessment of critical operating regimes. In particular, neglecting non-idealities such as axial dispersion can underestimate runaway risk and distort predicted stability limits. In this work, the impact of non-ideal plug flow behavior on reactor performance and stability is investigated by comparing ideal and axially dispersed PFR models within a sensitivity-based stability analysis (VMWT). The methodology is applied to the design of a multitubular reactor for the liquid-phase oxidation of benzyl alcohol to benzaldehyde. The results show how incorporating axial dispersion yields a more realistic stability picture while preserving computational efficiency, thereby supporting safer and more robust reactor design.