Summary One of the main challenges facing power generation by fuel cells involves the difficulties related to hydrogen storage. Several methods have been suggested and studied by researchers to overcome this problem. Among these methods, using fuel reformers as a component of the fuel cell system is a practical and promising alternative to hydrogen storage. Among many hydrogen carrier fuels used in reformers, methanol is one of the most attractive ones because of its distinctive properties. To design and improve of the methanol reformate gas fuel cell systems, different aspects such as promising market applications for reformate gas–fueled fuel cell systems, and catalysts for methanol reforming should be considered. Therefore, our goal in this paper is to provide a comprehensive overview on the past and recent studies regarding methanol reforming technologies, while considering different aspects of this topic. Firstly, different fuel reforming processes are briefly explained in the first section of the paper. Then properties of various fuels and reforming of these fuels are compared, and the characteristics of commercial reformate gas–fueled systems are presented. The main objective of the first section of the paper is to give information about studies and market applications related to reformation of various fuels to understand advantages and disadvantages of using various fuels for different practical applications. In the next sections of the paper, advancements in the methanol reforming technology are explained. The methanol reforming catalysts and reaction kinetics studies by various researchers are reviewed, and the advantages and disadvantages of each catalyst are discussed, followed by presenting the studies accomplished on different types of reformers. The effects of operating parameters on methanol reforming are also discussed. In the last section of this paper, methanol reformate gas–fueled fuel cell systems are reviewed. Overall, this review paper provides insight to researchers on what has been accomplished so far in the field of methanol reforming for fuel cell power generation applications to better plan the next stage of studies in this field.

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A steady state multiphysics model of a microchannel methanol reformer for hydrogen production was developed and validated to study the effects of catalyst layer structural parameters and heat supply strategies on the reformer performance. The hydrogen generated by the studied reformer was designated for use in high-temperature proton exchange membrane (HT-PEM) fuel cells. The dimensions of the reformer and inlet flow rate of methanol were selected to produce enough hydrogen to feed fuel cells in the 100 to 500 W range. The study considered a 2-dimensional domain for the thin coating of the reformingcatalyst to account for the internal diffusion limitations and the coating layer structural parameters. The multicomponent Maxwell−Stefan diffusion equation was implemented to account for diffusion fluxes inside the porous structure of the catalyst. The multiphysics model was validated using the reported experimental data by implementing four different reaction kinetics models of methanol steam reforming. The study considered the best fitted kinetics model to evaluate the performance of the microchannel methanol reformer. The results showed that the catalyst effectiveness factor was only relatively low at the entrance of the reformer for a catalyst layer thickness greater than 50 μm. In addition, the study revealed that for efficient use of the catalyst, the effective heat supply strategy should be improved. Additionally, the design feasibility of the segmented catalyst layer to achieve a certain amount of methanol conversion with less catalyst was demonstrated. It was determined, for the same inlet conditions, that the segmented catalyst layer design required 25% less reforming-catalyst to achieve 90% conversion compared to the conventional continuous coating design.

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