Aug 28, 2014

Kinetics of heterogeneous catalytic reactions: Analysis of reaction schemes

ai, thermodynamic activity of component i; Ai, preexponential factor for rate constant i; AI, chemical affinity for the step I; C°, concentration at standard state conditions; Csites, surface concentration of sites; CSTR, continuous-flow stirred tank reactor; Ei, activation energy; F, molecular flow rate of feed to reactor; Fs,i, molecular site velocity for species i in a flow reactor; Fi′′, number of gas-phase molecule colliding with a surface per unit area per unit time; Floc, fraction of gaseous local entropy; ΔG, change of Gibbs free energy; h, Plancks constant; ΔH, change of enthalpy; I1, I2, I3, moments of inertia about the principal axes; kB, Boltzmann constant; ki,for, ki, forward rate constant for reaction i; ki,rev, k−i, reverse rate constant for reaction i; k, Ki,eq, equilibrium constant for reaction i; m, mass of a molecule; NC, number of carbon atoms in surface species; Ni, number of molecules of species i in the reactor; Ng, number of gas-phase molecules; Nsat, number of adsorbed molecules at saturation; Nsite, number of catalytic sites; Ns,i, number of gaseous molecules for species i per site in a batch reactor; Pi, partial pressure of species i; PFR, plug flow reactor; Ptot, total pressure; ri, rate of the chemical reaction i or elementary step i; ri′′′, rate per unit reactor volume; , forward rate of elementary step i; Ri, rate of production of species i; R, gas constant; SA, surface area of active sites; ΔS, change of entropy; Strans,3D°,translational entropy of species with three degrees of translation freedom; Strans,2D°, translational entropy of species with two degrees of translation freedom;

Srot, rotational entropy; Svib, vibrational entropy; SR, number of catalytic sites in the reactor; XRC,i, degree of rate control for step i; V, volume; VR, volume of reactor; Zi, reversibility of step i; αH, linear variation of the adsorption heat with carbon number; φi, dimensionless sensitivity of the overall rate with respects to ki; ϱi,tot, total sensitivity with respect to ki; γ, activity coefficient; νi, vibrational frequency; ν‡, frequency factor; νij, stoichiometric coefficient for the j reactant and i elementary step; σr, rotational symmetry number; σ, sticking coefficient, symmetry number of a molecule; σi, stoichiometric coefficient of the linear combination of step i that leads to an overall stoichiometric reaction; τ, space time; , turnover frequency of reaction i; Ω, number of distinguishable configurations of a compound; °, standard state, degrees, inlet condition; ‡, activated complex.

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