Combination of Langmuir-Hinshelwood-Hougen-Watson and microkinetic approaches for simulation of biogas dry reforming over a platinum-rhodium alumina catalyst |
| |
Authors: | B. Sawatmongkhon K. Theinnoi T. Wongchang C. Haoharn A. Tsolakis |
| |
Affiliation: | 1. College of Industrial Technology, King Mongkut''s University of Technology North Bangkok, 1518 Pracharat 1 Road, Wongsawang, Bangsue, Bangkok, 10800, Thailand;2. Research Centre for Combustion Technology and Alternative Energy (CTAE), Science and Technology Research Institute, King Mongkut''s University of Technology North Bangkok, Thailand;3. School of Engineering, Mechanical and Manufacturing Engineering, University of Birmingham, Birmingham, B15 2TT, UK |
| |
Abstract: | Dry reforming of CH4 on a platinum-rhodium alumina catalyst is selected to numerically investigate biogas reforming process. Langmuir-Hinshelwood-Hougen-Watson (LHHW) rate expressions for dry reforming and reverse water-gas shift reactions are presented. Activation energies are estimated by combining microkinetics with the theory of unity bond index-quadratic exponential potential (UBI-QEP). Pre-exponential factors are initially obtained by using the transition state theory (TST) and optimised, later, by minimising errors between modelling and experimental data. Adsorption of CH4 on the catalyst surface is found to be the rate determining step in the range of relatively low temperature (600–770 °C), while at relatively high temperature (770–950 °C) the thermal cracking of adsorbed CH4 is the rate controlling step. Small effect of reverse water-gas shift reaction results in the ratio of H2 to CO produced less than unity for all operating conditions. The simulation shows that the dry reforming process proceeds with reaction rate far from equilibrium state. The presented mechanism is capable of predicting the dependence of biogas dry reforming activities (e.g., reactant conversions, product formations, H2 to CO ratio, and temperature profile inside the catalyst) on operating conditions (e.g., inlet temperature, heat supplied through the catalyst wall, and composition of biogas at inlet). |
| |
Keywords: | Biogas dry reforming Langmuir-Hinshelwood-Hougen-Watson approach Microkinetics On-board hydrogen production |
本文献已被 ScienceDirect 等数据库收录! |
|