The role of catalyst activity on the steady state and transient behavior of an industrial-scale fixed bed catalytic reactor for the partial oxidation of o-xylene on V2O5/TiO2 catalysts

Modeling of oxidative dehydrogenation of ethane to ethylene on a MoVTeNbO/TiO2 catalyst in an industrial-scale packed bed catalytic reactor

“…The o-xylene partial oxidation was selected since observations at industrial-scale with and without reaction are available from studies carried out by the research group [33,34,68]. Moreover, this reaction system presents the same geometric (L and d t /d p ) and operational conditions (Re p ) that are used for the ODH-Et reaction in this work, vide Table 3.…”

“…Some studies [33,34,45] suggest that the inclusion of velocity profiles improves heat transport description; however, others studies [68,[72][73][74] have neglected the influence of the hydrodynamics in the modeling of this type of reactors.…”

“…Due to this, this work simulates the performance of the MoVTeNbO catalytic formulation during the ODH-Et in a single tube industrial-scale packed bed reactor operating in a non-isothermal and non-adiabatic mode. The reliability of the simulations is based on the modeling approach proposed by Castillo-Araiza and López-Isunza [33,34,45], which allows the prediction of the observed behavior of a wall-cooled packed bed catalytic reactor with low d t /d p . This methodology accounts for the role of void fraction and hydrodynamics on heat transport in the reactor through the proper determination, using experiments in absence of reaction, of the effective heat transport parameters (HTP) such as the radial and axial effective thermal conductivities, k effr and k effz, respectively, and the wall heat transfer coefficient, h w .…”

“…4b). Both reaction cases compare temperature profiles along the reactor using distinct effective HTP estimated from the same set of experiments in absence of reaction: i) parameters estimated via the classical approach (CA) assuming an uniform velocity profile with constant void fraction [68,[72][73][74] and ii) parameter estimated via the boundary layer approximation (BLA) in which the role of void fraction profile and velocity field are assessed [33,34,45]. Table 3 presents the numerical values of h w and k eff estimated via the BLA and CA from the same experimental dataset.…”

“…The wall-cooled catalytic reactor with low tube-to-particle diameter ratio (d t /d p < 5) seems a suitable option to commercially achieve the ODH-Et over the MoVTeNbO formulation [24,25], since this configuration and catalyst design promote the fast removal of the heat generated, maximize the desirable product yield, and avoids strong catalyst deactivation by a sintering process [26][27][28][29][30][31][32][33][34], as observed for other well-known studied exothermic partial oxidation reactions. In fact, several researches [35][36][37][38][39][40][41] have considered the wall-cooled packed bed catalytic reactor for simulating the possible performance of the ODH-Et over catalytic systems different to the MoVTeNbO formulation.…”