Catalytic methanol steam reforming

Amphlett, J. C., Holland, R. M., Mann, R. F., and Pepply, B. A. Modeling a steady state catalytic methanol steam reformer for reactor development and... 

The catalytic combustor provides heat for the endothermic reforming reaction and the vaporization of liquid fuel. The endothermic reforming reaction is carried out in a parallel flow-type micro-channel of the reformer unit. It is well known that the methanol steam reforming reaction for hydrogen production over the Cu/ZnO/AbOs catalyst involves the following reactions [10]. Eq. (1) is the algebraic summation of Eqs. (2) and (3). 

Jacobs, G., Patterson, P.M., Graham, U.M., Crawford, A.C., Dozier, A., and Davis, B.H. 2005. Catalytic links among the water-gas shift, water-assisted formic acid decomposition, and methanol steam reforming reactions over Pt-promoted thoria. J. Catal. 235 79. 

It is worthy to note that numerous researchers have recently observed high catalytic activity for methanol steam reforming over Pd/Zn and Pt/Zn catalysts,528-534 and it would seem that these catalysts likely have potential for low temperature water-gas shift activity. 

In a later study, Pfeifer et al. [30] prepared Pd/Zn catalysts by both pre- and postimpregnation of wash-coated zinc oxide particles with palladium and compared their performance in methanol steam reforming. The catalytic performance of the samples was tested at a 250 °C reaction temperature, 3 bar pressure, a S/C ratio of two and 250 ms residence time. The WHSV amounted as 0.3 Ndm3 (min gcat) 1. The thickness of the coatings was calculated to 20 pm. The formation of the PdZn alloy was proven to occur at temperatures exceeding 200 °C by XRD measurements. 

Partial oxidation of propane (Coating characterization) Partial oxidation of propane Selective catalytic reduction of NOx (Coating characterization) Water gas shift Methane steam reforming Methanol steam reforming Schwarz et al. [178] Roumanie et al. [179] Pennemann et al. [183] Ercoli et al. [184] Stefanescu et al. [181] Germani et al. [177] Tonkovich et al. [182] Yu et al. [185]... 

Methanol steam reforming Catalytic combustion Partial oxidation of isoprene... 

C. Fukuhara, Y. Kamata, A. Igarashi, Catalytic performance of microtube-type copper-based catalyst for methanol steam reforming, prepared on the inner wall of an aluminum tube by electroless plating, Appl. Catal. A-Gen. 296 (2005) 100. 

Other microscale methanol steam reformers were developed, either heated by electricity [57] or coupled with a catalytic burner [58]. 

Men et al. reported the operation of a small-scale bread-board methanol fuel processor composed of electrically heated reactors [15]. A methanol steam reformer, two-stage preferential oxidation reactors and a catalytic afterburner were switched in series. A fuel cell equipped with a reformate-tolerant membrane, which had a 20 W nominal power output, was connected to the fuel processor and operated for about 100 h. 

First a 5 kW combined methanol steam reformer-catalytic combustor was built. The reactor was composed of modules ofthree types of plates forming a stack. Instead of microchaimels, fins served as mechanical support and improved heat transfer. A total of 225 plates were incorporated into the reactor. The reactor was designed for a maximum operating pressure of 4bar and 350 °C maximum reaction temperature. The experimental results presented were determined at a partial load of the device [1-2 kW for the lower heating value (LH V) of the hydrogen produced]. At a S/C ratio of... 

Shah and Besser presented results from their development work targeted at a 20 Wei methanol fuel processor-fuel cell system [66]. The layout of the system consisted of a methanol steam reformer, preferential oxidation, a catalytic afterburner and an evaporator. Vacuum packaging was the insulation strategy for the device, which is in line with other small-scale systems described above. A micro fixed-bed steam reformer coupled to a preferential oxidation reactor was then developed by the same group with a theoretical power output of 0.65 W. 

An exception in terms of catalysts is the catalytic partial oxidation or OSR of methanol due to the low reaction temperature required. Copper [25, 32-36] and palladium-zinc ahoy [36-38] have been proven to give high selectivities and space-time yields. For the latter system, the palladium forms an alloy with the zinc oxide support under reducing conditions above 300 °C and is stable under the reaction conditions of methanol steam reforming [39]. However, the stability of the ahoy under CPO has not been proven so far by X-ray diflraction after exposure to reaction conditions. 

Casio Computer has developed a 2.4 We integrated micro fuel processor comprising a methanol steam reformer, a PrOx reactor and a catalytic combustor (Figures 27.10... 

Also under oxidizing conditions, like the partial oxidation of methanol to hydrogen, water, and CO2, intermetallic compounds can be formed. As in the case of methanol steam reforming over Pd/ZnO, the intermetallic compound ZnPd is part of the catalytic system Pd-Zn/Al203 under these conditions (125). The observation of intermetallic compounds is not limited to oxidation reactions involving methanol. Also in the oxidation of aldoses such as lactose and glucose over... 

Catillon, S, Louis, C, Topin, F, Vicente, J, Rouget R. Improvement of methanol steam reformer for FI2 production by addition of copper foam in both the evaporator and the catalytic reactors. Chem. Eng. Trans. 2004 4 111-116. 

Kolb, G., Keller, S., Pecov, S., Pennemann, H., and Zapf, R. (2011) Development of micro-structured catalytic wall reactors for hydrogen production by methanol steam reforming over novel Pt/In203/Al203 catalysts. Chem. Eng. Trans., 24, 133-138. 

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