2 - Membrane reactors for methane steam reforming (MSR)

Abstract

Methane steam reforming (MSR) is the most common and cost-effective method for hydrogen production, and it contributes about 50% of the world's hydrogen production. Although MSR is a mature technology, it suffers from significant disadvantages such as mass and heat transfer issues and coke deposition during the reaction. Industrially, the MSR reaction is carried out in conventional reactors (CRs) and, in order to obtain a highly pure hydrogen stream, several steps are necessary, such as the reduction of carbon monoxide content in the reformate stream by water gas shift reactors, pressure swing adsorption, and further hydrogen separation/purification devices. Therefore, in order to intensify the whole process, a membrane reactor can be used as alternative solution to conventional systems. In particular, the use of a hydrogen perm-selective membrane inside of a reactor allows the combination of the chemical reaction and hydrogen separation in only one tool. As a result, high-purity hydrogen, methane conversion, and hydrogen production enhancement are obtained as well as the possibility to perform the MSR reaction at milder operating conditions than CRs. Therefore, in this chapter, the relevant progress achieved so far, the most relevant topics of MSR via membrane reactor technology, and the effects of the most important parameters affecting MSR in membrane reactors are described and critically reviewed. In addition, an overview on the mathematical models used for simulating the MSR reaction in a membrane reactor is also presented and discussed.