Chemical Engineering Science, Vol.94, 214-223, 2013
Hydroconversion of an atmospheric residue with a dispersed catalyst in a batch reactor: Kinetic modeling including vapor-liquid equilibrium
A kinetic model was proposed to describe the atmospheric residue hydroconversion with a dispersed catalyst in a batch reactor. The model, taking into account the gas-liquid mass transfer, includes hydrogen and five lumps: remaining residue (> 510 degrees C), VGO (350-510 degrees C), distillate (180-350 degrees C), naphtha (40-180 degrees C), and gas. Vapor-Liquid Equilibrium (VLE) was determined by performing an adiabatic flash with PROII software. Atmospheric residue fractions reacted with active hydrogen species (activated by dispersed MoS2 catalysts in-situ generated from a precursor) to give lighter fractions, such as naphtha and gas oil were produced with almost no coke formation. The experiments of atmospheric residue hydroconversion were performed under the reaction conditions of 420 or 430 degrees C, an initial partial pressure of hydrogen of 15 MPa, and different reaction times. Stoichiometric coefficients, kinetic parameters and the mass transfer coefficient (k(L)a) were estimated using a nonlinear least-squares regression of the experimental results. The calculated apparent activation energies and the contribution of hydrogen concentration via the Hatta number in liquid phase on hydroconversion were discussed. (c) 2013 Elsevier Ltd. All rights reserved.
Keywords:Kinetic modeling;Lumps models;Dispersed catalysts;Mass transfer coefficient (K(l)a);Hatta number