(516h) Enhanced Water Gas Shift Reaction By Incorporating a Pd60-Cu40 Membrane Reactor

Hydrogen has recently received wide attention due to its several benefits, including its environmental friendliness and carbon free emissions upon combustion. Its cost should be further reduced so that it can be more widely available in the global energy mix. The conventional hydrogen production system, i.e., steam methane reforming, requires several processes reforming followed by combination of water-gas-shift (WGS) reactors and pressure swing adsorption. Process integration can help in optimizing the process further and also help reduce hydrogen production costs. Our system first involves a high-pressure, high-temperature steam reformer that reforms liquid fuel to produce a stream rich in H₂ and CO. The stream enters a membrane reactor (MR), where WGS reactions and H₂ separation occur simultaneously. The high-pressure operation of the MR allows hydrogen to permeate, enhancing hydrogen production due to Le Chatelier’s Principle. In order to experimentally observe this effect, we used a commercial Fe-Cr catalyst and observed its effects on the MR performance. Two experiments, the catalyst as a packed bed reactor and our lab-scale membrane reactor filled with the catalyst, were performed. A lab-scale MR with the reformate gas mixture of a steam reformer (H₂: 41.1% H₂O: 30.6%, CH₄: 1.8%, CO₂: 7.4%, CO: 9.1%, N₂: 10%). The pressure, temperature, and GHSV of the experiments were 2-10 bar(g), 400°C, and 2,000 h^-1, respectively. By comparing the results of the two cases above, the MR with the catalyst clearly led to higher CO conversion than the catalyst by itself. These findings can be used for building our proposed system on a larger scale.