Proton-conducting membrane reactor

J. Li, H. Yoon, T. Oh, E. D. Wachsman, High temperature SiCeo,9Euo.i03 6 proton conducting membrane reactor for H2 production using the water-gas shift reaction, Appl. Catal. B Environ. 

Karagiannakis G, Kokkofitis C, Zisekas S and Stoukides M (2005), Catalytic and electrocatalytic production of H2 from propane decomposition over Pt and Pd in a proton-conducting membrane-reactor , Catal Today, 104,219-224. 

Karagiannakis G, Zisekas S, Kokkofitis C and Stoukides M (2006), Effect of H2O presence on the propane decomposition reaction over Pd in a proton conducting membrane reactor , AppZ Catal A-Gen, Mil, 265-271. 

Li, J., Yoon, H., Wachsman, E. D. (2012). Carbon dioxide reforming of methane in a SrCeo.7Zro.2Euo.1O3a proton conducting membrane reactor. International Journal of Hydrogen Energy, 37(24), 19125-19132. 

Table 6.6 Ammonia synthesis in proton-conducting membrane reactors... 

When the membrane is a pure proton conductor, the electrons released from the chemical reactions have to be transported to the oxygen-rich side via an external circuit so that the reaction can proceed, as shown in Rg. 7.6b. Therefore, electrical power can be co-generated along with the production of C2 compounds, and the membrane reactor becomes a SOFC-type one. Since the catalytic activity of the membrane surface is poor, a catalyst layer is often required in the proton conducting membrane reactors. 

Selective oxidation of n-paraffins has been carried out on catalytic iono-mer membranes with Fe +/H202 Fenton.The three-phase membrane reactors were constituted by a proton-conducting membrane (based on Nafion), fed on one side with a gaseous n-paraffins and, on the other side, with an aqueous solution of hydrogen peroxide and Fe " ions. The paraffin is activated by... 

Key words membrane reactor, perovskite, proton conducting membrane, mixed ionic-electronic conductor (MIEC), partial oxidation of methane... 

Figure 18.2 Schematic illustration of operating principles in sohd-state membrane reactors (a) proton-conducting membrane, and (b) oxide-ion membrane (Amar et al., 2011).

The double-chamber reactor is a typical cell reactor in which the anode and the cathode are exposed to different gas mixtures. A schematic diagram of a double-chamber reactor with a proton-conducting membrane is presented in Figure 18.3. 

Finally, the proton-conducting membranes based on perovskites can be used for steam permeation. Such a concept has been demonstrated for fuel cells operating at zero current, but could also be extended to membrane reactor applications [65]. In this concept, water permeates from the feed to the permeate side of the membrane, promoting steam reforming of methane. The generated H2 splits at the permeate/membrane surface, permeating back to the feed side as a Fara-daic flux and reacting with O2. 

Proton-conducting membranes can be applied to reduce NO emission by combining heterogeneous catalysis and solid-state electrochemistry. The solid electrolytes in membrane reactors serve to control chemisorp-tive bonds electrochemically and enhance catalytic activity. Figure 6.8 shows a schematic diagram of a steam electrolysis cell constructed with a proton conductor for reducing NO. Steam is electrolyzed at the anode. The electrode reactions are... 

Fu, X.-Z., Luo, J.-L., Sanger, A.R., Xu, Z.-R. and Chuang, K.T. (2010) Fabrication of bi-layered proton conducting membrane for hydrocarbon solid oxide fuel cell reactors. Electrochimica Acta, 55,1145-1149. 

Key words membrane reactors, mixed ionic-electronic conductors (MIECs), perovskite, oxygen permeable membrane, proton conducting membrane. 

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