Oxidative reforming

There have been a number of cell designs tested for this reaction. Undivided cells using sodium bromide electrolyte have been tried (see, for example. Ref. 29). These have had electrode shapes for in-ceU propylene absorption into the electrolyte. The chief advantages of the electrochemical route to propylene oxide are elimination of the need for chlorine and lime, as well as avoidance of calcium chloride disposal (see Calcium compounds, calcium CHLORIDE Lime and limestone). An indirect electrochemical approach meeting these same objectives employs the chlorine produced at the anode of a membrane cell for preparing the propylene chlorohydrin external to the electrolysis system. The caustic made at the cathode is used to convert the chlorohydrin to propylene oxide, reforming a NaCl solution which is recycled. Attractive economics are claimed for this combined chlor-alkali electrolysis and propylene oxide manufacture (135). 

Ahmed, S. (1997). Partial Oxidation Reformer Development for Fuel Cell Vehicles. Proceedings of the. 12nd Intersociety Energy Conversion Engineering Conference. Paper 97081 (August). 

A growing number of research groups are active in the field. The activity of reforming catalysts has been improved and a number of test reactors for fuel partial oxidation, reforming, water-gas shift, and selective oxidation reactions were described however, hardly any commercial micro-channel reformers have been reported. Obviously, the developments are still inhibited by a multitude of technical problems, before coming to commercialization. Concerning reformer developments with small-scale, but not micro-channel-based reformers, the first companies have been formed in the meantime (see, e.g., ) and reformers of large capacity for non-stationary household applications are on the market. 

Chen, C. et al., Conversion of methane to syngas by a membrane-based oxidation reforming process, Angew. Chem. Int. Ed., 42, 5196, 2003. 

Ahmed, S. et al., Catalytic partial oxidation reforming of hydrocarbon fuels, Proc. of 1998 Fuel Cell Seminar, Palm Springs, CA, 242,1998. 

A POX reformer also can be used for converting gaseous fuels, but does not produce as much hydrogen as the steam reformers. For example, a methane-fed POX reformer would produce only about 75% of the hydrogen (after shifting) that was produced by an SR. Therefore, partial oxidation reformers are typically used only on liquid fuels that are not well suited for steam reformers. Partial oxidation reformers rank second after steam reformers with respect to their hydrogen yield. For illustration, the overall POX reaction (exothermic) for methane is... 

Liquid fuels such as distillate, naphtha, diesel oils, and heavy fuel oil can be reformed in partial oxidation reformers. All commercial POX reactors employ noncatalytic POX of the feed stream by oxygen in the presence of steam with reaction temperatures of approximately 1,300 to 1,500°C (2,370 to 2,730°F) (18). For illustration, the overall POX reaction for pentane is... 

Table 9-3 Typical Partial Oxidation Reformed Fuel Oil Reformate (18)...

Hydrogen Burner Technology (HBT) (28) was founded to bring to market reformer systems based on the principles of under-oxidized combustion (E OB ). These systems use either non-catalyzed partial oxidation reformers or catalyzed autothermal reformers. The systems for fuel cell applications include all of the components required to deliver anode-ready gas and to... 

Private communication with Johnson Matthey Technology Centre, Reading, England, February 2000. 17. "Catalytic Partial Oxidation Reforming of Hydrocarbon Fuels," S. Ahmed, et al., ANL, Pg. 242, Fuel Cell Seminar Abstracts, Courtesy Associates, Inc., November 1998. 

Figure 3 Thermal integration of reformer with fuel cell system (a) Catalytic partial oxidation reformer, (b) Catalytic steam reformer, and (c) Autothermal reformer...

Table 1 also indicates that the two alcohols (methanol and ethanol) are reformed at substantially lower temperatures than the other species. Of the fuels considered for partial oxidation reforming, alcohols should be considerably easier to reform since they are already partially oxidized. 

Figure 4. Hydrogen production from partial oxidation reforming of cyclohexane and toluene using ANL catalyst.

Figure 5. Product distribution from partial oxidation reforming of premium gasoline using the ANL catalyst.

Figure 8. Results from bench-scale partial oxidation reformer demonstrating the rapid response to a demand for increased power.

E-coat was applied within a minute after the CRS panel was taken from the plasma reactor. The surface contains a small but unknown amount of oxide reformed during this transfer process. 

Lutz, A., Bradshaw, R., Bromberg, L., Rabinovich, A. (2004). Thermodynamic analysis of hydrogen production by partial oxidation reforming. Int.. Hydrogen Energy 29, 809-816. 

Chen, G., Li, S., and Yuan, Q. Pd-Zn/Cu-Zn-Al catalysts prepared for methanol oxidation reforming in microchannel reactors. Catalysis Today, 2007, 120 (1), 63. 

Alvarez-Galvan, M.C., Navarro, R.M., Rosa, F., Briceno, Y., Ridao, M.A., and Fierro, J.L.G. Hydrogen production for fuel cell by oxidative reforming of diesel surrogate Influence of ceria and/or lanthana over the activity of Pt/Al203 catalysts. Fuel, 2008, 87 (12), 2502. 

Lyubovsky, M. and Roychoudhury, S. Novel catalytic reactor for oxidative reforming of methanol. Applied Catalysis. B, Environmental, 2004, 54 (4), 203. 

Fierro, V., Klouz, V., Akdim, O., and Mirodatos, C. Oxidative reforming of biomass derived ethanol for hydrogen production in fuel cell applications. Catalysis Today, 2002, 75 (1—4), 141. 

Velu, S., Satoh, N., Gopinath, C.S., and Suzuki, K. Oxidative reforming of bio-ethanol over CuNiZnAl mixed oxide catalysts for hydrogen production. Catalysis Letters, 2002, 82, 145. 

Figure I. Catalytic performance in oxidative reforming of methane (a-c) as a function of time on stream and relationship between carbon deposition and deactivation rate (d).

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