(453a) Clean Energy Conversion By Process Intensification Via Membrane Rector

In the view of a significant reduction of greenhouse gases emissions amidst fossil fuel exploitation, the use of sustainable energy sources is a mandatory option as well as the use of alternative fuels for the transportation sector and power and heat sectors for both buildings and industry [1]. In this context a strong interest has been addressed towards the possible development of a global ‘hydrogen economy’, by considering hydrogen as the energy carrier of the future [2]. Among all of the different technologies to produce green and sustainable hydrogen, inorganic membrane reactors (MRs) are a promising alternative to enable distributed and decentralized hydrogen [3].

Inorganic (MRs) are a clear example of process intensification, and their utilization provides several other benefits when applied to chemical processes. Specifically, they are able to reduce the equipment footprint, energy consumption, and environmental impact of manufacturing processes. For these reasons, they may be applied to NH₃ cracking (decomposition) or to reforming reaction of bio-sources to produce clean hydrogen [4-5]. Indeed, in a single unit operation, MRs deliver high purity hydrogen (by the permeation of hydrogen through the membrane wall) and a separate concentrated CO₂ stream that can be sequestered. Since the MR is an open system, hydrogen is constantly produced via the targeted reaction and removed from the reaction zone through the H₂-selective membrane allowing for the equilibrium conversion to proceed to near completion, while also separating the H₂ from the CO₂.

In general, inorganic membranes have the potential to play a critical role in the area of clean energy conversion and the study of different materials through alloying is the key to reaching high MR performance. In this regard, the present study reviews the most relevant scientific results on hydrogen production from bio-sources reforming processes and ammonia decomposition performed in MRs technology. The benefits and the main drawbacks of inorganic MRs are examined and the performances in terms of hydrogen yield, hydrogen recovery, and conversion are qualitatively compared to those of conventional systems.

References

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