Intraparticle Mass and Heat Transfer Modeling of Methanol to Olefins Process on SAPO-34: A Single Particle Model

Abstract

Light olefins such as ethylene and propylene are high value-added gases usually derived from petroleum refining. The methanol to olefins (MTO) process offers an attractive alternative route to produce olefins, as methanol can be prepared from a relatively cheap and widely available source of energy, i.e., coal or natural gas. In the present work, a comprehensive single particle model was developed to characterize detailed chemical and physical phenomena occurring within a SAPO-34 catalyst particle during the MTO process. This model allows prediction of the species mass fraction, temperature, reaction rate, and pressure distributions within the particle as a function of particle diameter, operating temperature, mean intraparticle pore diameter, and thermal conductivity. A thorough parametric study based on the validated model demonstrated that intraparticle phenomena have a great impact on the MTO process and thus cannot be neglected in MTO process modeling, especially for the cases where fast or strong exothermal reactions occurred in large catalytic particles.

Numerical evaluation on the intraparticle transfer in butylene oxidative dehydrogenation fixed-bed reactor over ferrite catalysts

“…The PMM is used to describe the gas-solid flow in the fixed-bed reactor, and the SPM is used to represent the intraparticle transfer and reaction. These models are briefly summarized in Tables 1 and 2 [22][23][24][25][26][27][28]. The average gas velocity is approximately 0.033 m/s in the porous medium, and the numerical Re number is close to 6.…”

“…The effectiveness factor is defined as the ratio of the actual reaction rate to the surface reaction rate of the particle. In previous modeling studies, the effectiveness factor was regarded as 1 when the surface reaction rate is 0 [14,16,28]. If the intrinsic reaction rate is zero, the reaction effectiveness factor is defined as 1 in this study.…”

“…6). Given the intraparticle transfer limitation, the concentration of the reactant gradually decreases from the particle surface to the particle center [28]. Consequently, the concentration gradient within the catalyst particles reduces the average reaction rate, and the concentration of reactant for case 2 is higher than that for case 1.…”

Particle Behavior in FBRs: A Comparison of the PBM-CFD, Multi-Scale CFD Simulation of Gas-Solid Catalytic Propylene Polymerization

“…Based on first principles, the intraparticle governing equations are usually composed of mass, energy, and momentum balances as well as the auxiliary equations of state for gases, species reaction kinetics, multicomponent diffusion, etc. [26,27] However, there is only a reactant component (i.e. propylene) in the propylene polymerization system.…”

Modeling of Multiprocess Behavior for Feedstock-Mixed Porous Pellet: Heat and Mass Transfer, Chemical Reaction, and Phase Change

“…A one-dimensional mathematical model describing the heat and mass transfer processes in the oxidation process of uranium carbide fuel pellet was built and the effect of gas temperature and oxygen concertation on reactions was analyzed . Thermodynamics and kinetics of the limestone decomposition process were analyzed and the corresponding mathematical model was developed. , The influence of pore size and porosity on the heat and mass transfer behavior for the MTO catalyst particle was investigated by a comprehensive single particle model, and their optimal distributions were obtained. , Additionally, a mesoscale multiregion model for the reaction-diffusion process was developed to study the reaction-diffusion processes in catalyst pellets with micropore and meso-/macropore …”