Membrane reactors for sustainable production of fuels and value-added chemicals: Innovations, challenges and future directions

The production of renewable fuels and value-added chemicals has drawn extensive attention worldwide as an alternative to those derived from fossil fuels. However, conventional production processes typically involve energy-intensive chemical purification methods. In contrast, membrane reactors (MRs) are regarded as one of the most promising technologies in this field. They possess the capability to efficiently and cost-effectively separate chemical mixtures, presenting a wide range of application prospects and enabling the use of sustainable materials as alternatives to fossil fuels. This paper provides an overview of the features and classification of membrane reactors, concentrating on how MRs improve existing production processes. It comprehensively summarizes the state-of-the-art studies on the utilization of MRs in renewable fuel and chemical production. Additionally, it compares the advantages and environmental benefits of membrane reactors with conventional techniques, emphasizing various applications including hydrogen/syngas production through steam methane reforming/partial oxidation, water-gas shift reaction, and ammonia decomposition; as well as value-added chemicals such as methane, olefin, methanol produced via CO₂ hydrogenation, alkanes dehydrogenation, and oxidative coupling of methane. Furthermore, this paper addresses current challenges associated with MRs while providing an overview of future development prospects in this area.