Ultra-pure hydrogen production via ammonia decomposition in a catalytic membrane reactor

Adsorbents Development for Hydrogen Cleanup from Ammonia Decomposition in a Catalytic Membrane Reactor

“…The sorbent showing the best performance both in terms of cyclability and useful capacity during NH 3 -TPD was further tested at ambient pressure in a dedicated setup in which it was exposed to a gas stream simulating a typical composition of the permeate stream leaving a Pdbased membrane reactor for the production of NH 3 -derived hydrogen [7,8]. A schematic representation of the experimental setup used can be found in the supplementary material of this work.…”

“…The sorbent adsorption and regeneration experiments were then started. Based on the results of our previous works [7,8], the permeate of a typical membrane reactor for hydrogen production via ammonia decomposition was selected to be a stream of 0.7 L N /min of hydrogen containing 10.0 ppm of NH 3 . In the experimental tests carried out in this work, this stream was reproduced by appropriately diluting a stream of hydrogen containing 95.7 ± 5 ppm NH 3 with a pure hydrogen stream.…”

“…In order to overcome the challenges related to hydrogen transportation and storage, one alternative consists in storing hydrogen in the form of liquid fuels [2][3][4] which could be then decomposed to produce hydrogen when required [5,6]. In this regard, ammonia has recently gained attention as the potential ideal candidate for the storage of hydrogen [3,6,15,[7][8][9][10][11][12][13][14] to be used as feedstock for PEMFCs, [16][17][18][19][20][21][22][23][24] as the absence of carbon in its molecular structure minimizes the risk of CO poisoning of the PEMFCs electrodes [25] and prevents the release of CO 2 . Moreover, its relatively low cost, ease of liquefaction as well as its already existing infrastructure for storage and transportation allow for an economically competitive, relatively easy and safe hydrogen storage and transportation [3,6,[10][11][12].…”

“…Membrane reactors for ammonia decomposition have already been experimentally investigated in literature, generally employing ruthenium-based (Ru-based) catalysts to promote the ammonia decomposition reaction and palladium-based (Pd-based) membranes for hydrogen separation [5,7,8,14,23,28,30,32,36]. It has been demonstrated that with a membrane reactor it is possible to achieve higher ammonia conversions than in conventional system even at lower temperatures while simultaneously recovering large part of the hydrogen produced [8,28,30].…”

“…Since this specification is not always met when hydrogen is produced via ammonia decomposition in a membrane reactor [5,8,14], strategies must be implemented in order to increase the hydrogen purity by reducing the residual ammonia concentration in the hydrogen stream. In our previous work [7], it was experimentally demonstrated that a possible alternative to produce a ultra-pure hydrogen stream consists in a small adsorption unit downstream the membrane reactor. Specifically, a bed of zeolite 13X at ambient conditions was demonstrated to be effective for hydrogen purification from residual ammonia.…”