Monte Carlo Simulation of First-Order Diffusion-Limited Reaction within Three-Dimensional Porous Pellets

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Monte Carlo Simulation of First-Order Diffusion-Limited Reaction within Three-Dimensional
Porous Pellets

GUO Xiangyun^a; F.J.Keil^b

^a State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of
Sciences, Taiyuan 030001, China
^b Hamburg University of Technology, Chemical Reaction Engineering, Eissendorfer Str. 38, D
-21071, Hamburg, Germany

Received:1900-01-01 Revised:1900-01-01 Online:2003-08-28 Published:2003-08-28
Contact: GUO Xiangyun

三维多孔颗粒中一级扩散和反应过程的蒙特卡罗模拟

郭向云^a; F.J.Keil^b

^a State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of
Sciences, Taiyuan 030001, China
^b Hamburg University of Technology, Chemical Reaction Engineering, Eissendorfer Str. 38, D
-21071, Hamburg, Germany

通讯作者: 郭向云

Abstract

Abstract: The Monte Carlo method was employed to simulate diffusion and reaction processes within
three-dimensional porous catalyst pellets. The porous pellets used were represented by a
Menger sponge and a uniform-pore structure respectively. Results obtained from the fractal
pellet showed an intermediate low-slope asymptote inthe logarithmic plot of reaction rate
and reaction probability. However, the low-slope one did not appear when thereaction
occurred within the uniform pellet. Moreover, it was certified that the fractal structure
not only generateda new asymptote, but also reduced diffusion resistance of reactants and
products.

Key words: Monte Carlo method, reaction-diffusion, fractal structure, low-slope asymptote, concentration distri-bution

摘要： The Monte Carlo method was employed to simulate diffusion and reaction processes within
three-dimensional porous catalyst pellets. The porous pellets used were represented by a
Menger sponge and a uniform-pore structure respectively. Results obtained from the fractal
pellet showed an intermediate low-slope asymptote inthe logarithmic plot of reaction rate
and reaction probability. However, the low-slope one did not appear when thereaction
occurred within the uniform pellet. Moreover, it was certified that the fractal structure
not only generateda new asymptote, but also reduced diffusion resistance of reactants and
products.

关键词: Monte Carlo method;reaction-diffusion;fractal structure;low-slope asymptote;concentration distri-bution

GUO Xiangyun, F.J.Keil. Monte Carlo Simulation of First-Order Diffusion-Limited Reaction within Three-Dimensional
Porous Pellets[J]. .

郭向云, F.J.Keil. 三维多孔颗粒中一级扩散和反应过程的蒙特卡罗模拟[J]. CIESC Journal.

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