(464c) Hydrogen Production in Pd-Based Membrane Reactor Via Reforming Reactions

In the last decades, the excessive use of fossil fuels to produce energy, as well as the growth of environmental pollution due to green house gases (GHGs) and other harmful emissions has led to the development of new technologies and to the utilization of renewable sources. In this context, hydrogen is recognized as one of the most promising energy carriers of the future. Unfortunately, hydrogen is not available in the Earth in elementary form and is currently produced primarily from steam reforming of natural gas, an energy-intensive process.

Nowadays, different methods, such as alcohols reforming reactions, and alternative devices, such as membrane reactors (MRs), are covering an important role for hydrogen production/separation. Specifically, alcohols as ethanol, methanol, glycerol etc. are largely available from renewable sources and they could be used as “bio-feedstocks” for hydrogen generation via reforming reactions, while MR technology seems to represent a valid choice for replacing the conventional process due to its ability to provide the generation and separation of pure hydrogen in a single stage [1]. Among several renewable sources, bioethanol has received considerable attention due to its potential environmental benefits [2].

In the last years, Pd-based composite membranes, i.e. thin metallic layer supported on such porous materials as ceramics or stainless steel, have been considered owing to their lower cost (thin Pd layer) and higher mechanical resistant (porous support) than dense Pd-based ones [3]. Moreover, the use of Pd-alloys, in particular, with Ag, Au, Pt, is grown in the last years given their ability to enhance the hydrogen permeability and to resist sulfur poisoning.

Hence, the current study reviews the most relevant scientific results on hydrogen production from bio-ethanol reforming processes performed through membrane reactor technology. The benefits and the main challenges of inorganic membrane reactors, when applied to ethanol-reforming processes, are examined and the performances in terms of hydrogen yield, hydrogen recovery, and conversion are compared to those of conventional systems.

References

[1] A. Iulianelli, S. Liguori, A. Vita, C. Italiano, C. Fabiano, Y. Huang, A. Basile, The oncoming energy vector: hydrogen produced in Pd-composite membrane reactor via bioethanol reforming over Ni/CeO₂ catalyst, Catal. Today, 259 (2015) 368-375

[2] T. Yamazaki, et al., Behavior of steam reforming reaction for bio-ethanol over Pt/ZrO₂ catalysts, Appl. Catal. B: Environ. 99 (2010) 81-88.

[3] S. Liguori, et al., Performance of a Pd/PSS membrane reactor to produce high purity hydrogen via WGS reaction. Catal. Today, 193 (2012) 87-94.