Fundamental Kinetic Modeling of Catalytic Reforming

Abstract

A fundamental kinetic model for the catalytic reforming process has been developed. The complex network of elementary steps and molecular reactions occurring in catalytic reforming was generated through a computer algorithm characterizing the various species by means of vectors and Boolean relation matrices. The algorithm is based on the fundamental chemistry occurring on both acid and metal sites of a Pt-Sn/Al 2 O 3 catalyst. The number of rate coefficients for the transformations occurring on the metal sites was reduced by relating them to the nature of the involved carbon atoms. The single event concept was applied in the development of rate expressions for the elementary steps on the acid sites. This approach allows obtaining rate coefficients that are independent of the feedstock, owing to their fundamental chemical nature. The Levenberg-Marquardt algorithm was used to estimate the rate coefficients. The estimation was based on data reported from a previous naphtha reforming study in a fixed bed reactor with Pt-Sn/Al 2 O 3 as a catalyst. The agreement between the experimental and estimated yields is excellent. The statistical tests were also satisfied. The kinetic model was used in pseudo-homogeneous and heterogeneous reactor models simulating an industrial three-bed adiabatic catalytic reformer with centripetal radial flow.

Ethene oligomerization on Ni-SiO2-Al2O3: Experimental investigation and Single-Event MicroKinetic modeling

“…The latter accounts for the number of indistinguishable manners in which an elementary step can occur and depends on the structural differences between the reactants and the transitition state. This methodology is already applied successfully to hydroconversion [9,23], alkylation [24], catalytic cracking [25], catalytic reforming [26], methanol to olefins [27,28], FischerTropsch synthesis [29], hydrogenation of aromatics [30] and xylene isomerization [31]. Within such SEMK models, a distinction is made between catalyst and kinetic descriptors, the former being related to the catalyst properties, e.g., acid site strength through the protonation enthalpy, while the latter are reaction specific, e.g., activation energies and pre-exponential factors.…”

A Review of Kinetic Modeling Methodologies for Complex Processes

“…This modeling approach has been applied for acid-catalyzed processes such as: -isomerization (Guillaume et al, 2003a,b,c;Surla et al, 2004Surla et al, , 2011, -alkylation (Martinis and Froment, 2006), -olefin oligomerization Shahrouzi et al, 2008;Toch et al, 2015), -methanol-to-olefins Froment, 2001a,b, 2004;Kumar et al, 2013a,b), -catalytic reforming (Sotelo-Boyás and Froment, 2009;Cochegrue et al, 2011), -catalytic cracking Dewachtere et al, 1999;Beirnaert et al, 2001;Moustafa and Froment, 2003;Quintana-Solórzano et al, 2005, 2007a,b, 2010Xue et al, 2014), -hydrocracking (Baltanas and Froment, 1985;Baltanas et al, 1989;Vynckier and Froment, 1991;Svoboda et al, 1995;Schweitzer et al, 1999;Martens and Froment, 1999;Martens et al, 2000Thybaut et al, 2001Thybaut et al, , 2009Thybaut and Marin, 2003;Laxmi Narasimhan et al, 2003a, 2007Chavarría-Hernández et al, 2004Valéry et al, 2007;Kumar and Froment, 2007a,b;Chavarría-Hernández and Ramírez, 2009;Mitsios et al, 2009;Choudhury et al, 2010;Vandegehuchte et al, 2012Vandegehuchte et al, , 201...…”

Toward enhanced hydrogen production in a catalytic naphtha reforming process

“…In literature, there are two distinct concepts for modeling CNR kinetics: the "lumped" [9e24], and (ii) the single-event model [26]. The "lumped model" concept utilizes pseudo-components (lumps) in kinetic expressions instead of real components.…”