Steam reforming of methanol

Steam Reforming of Methanol. — The steam reforming of methanol43 has been developed as a convenient method of producing pure hydrogen according to the equation  

The process is generally carried out at relatively low temperature of 250-350 °C, when the direct decomposition of methanol  

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Fig. 5. Change of the open-circuit potential with time for steam reforming of methanol over the 30 wt% Ni-SDC and 30 wt% Ni-YSZ electrode-catalyst. Upper Ni-SDC lower Ni-YSZ. Operating conditions 800 °C, 1 atm, H20/CH30H = 2, space time = 0.37 s [9].

S. Velu, K. Suzuki, M. Okazaki, M. P. K oor, T. Osaki, andF. Ohashi, Oxidative steam reforming of methanol over CuZnAl(Zr)-oxide catalysts for flie selective production of hydrogen for fuel cells Catalyst characterization and performance evaluation, J. Catal. 194,373 (2000). 

M. M. Gunter, T. Ressler, R. E. lentoft, and B. Bems, Redox behavior of copper oxide catalysts in the steam reforming of methanol studied by in situ X-ray diffraction and absorption spectroscopy, J. Catal. 203, 133-149 (2001). 

SCR Selective catalytic reduction SRM Steam reforming of methanol UV Ultraviolet... 

However, one application where gold could be most applied is in fuel cells used in electric vehicles, with operating temperatures of 80-100 °C. Another field of application for supported gold catalysts is the production of hydrogen by steam reforming of methanol. 

Currently, low-temperature CO oxidation over Au catalysts is practically important in connection with air quality control (CO removal from air) and the purification of hydrogen produced by steam reforming of methanol or hydrocarbons for polymer electrolyte fuel cells (CO removal from H2). Moreover, reaction mechanisms for CO oxidation have been studied most extensively and intensively throughout the history of catalysis research. Many reviews [4,19-28] and highlight articles [12, 29, 30] have been published on CO oxidation over catalysts. This chapter summarizes of the state of art of low temperature CO oxidation in air and in H2 over supported Au NPs. The objective is also to overview of mechanisms of CO oxidation catalyzed by Au. 

Figure 2.12 Methanol conversion vs. temperature for steam reforming of methanol. (A) 4.8, ( ) 9.0 and ( ) 16.7 wt.% Pt on ZnO (both filled and open squares) 0.1925 gcatalyst, 100 ms contact time, 36 000 GHSV, H20/C = 1.8 and 1 atm [31] (by courtesy of Elsevier Ltd.).

Chin, Y.-H., Dagle, R., Hu, J., Dohnalkova, A. C., Wang, Y., Steam reforming of methanol over highly active Pd/ZnO catalyst, Catal. Today 2002, 77, 79-88. 

Men, Y., Gnaser, H., Zapf, R., Kolb, G., Hessel, V., Ziegler, C., Parallel screening of Cu/Ce02/y-Al203 for steam reforming of methanol in a 10 channel micro-reactor, Catal. Commun. 2004, submitted for publication. 

Cremers, C., Dehlsen, J., Stimming, U., Reuse, P., Renken, A., Haas-Santo, K., Gorke, O., Schubert, Micro structured-reactor-system for the steam reforming of methanol, in Proceedings of the 7th International Conference on Microreaction Technology, IMRET 7 (7-10 Sept. 2003), Lausanne, 2003, 56. 

It follows that most work reported over the last few years on steam reforming and methanation has been concerned with nickel catalysts. The following sections will therefore deal mostly with nickel-based catalysts, particularly those which have some importance in commercial practice. Particular stress will be laid on work, with which the author has been associated, concerned with steam reforming and methanation catalysts but mention will also be made of parallel studies from other laboratories. In sections on the catalysts for steam dealkylation and steam reforming of methanol, where catalyst selectivity is a prerequisite, other types of catalyst will also be discussed. 

Methanol steam-reforming is normally carried out in the range between 250°C-350°C, depending on the reforming process, and the catalyst usually applied is Cu/ZnO [151], The chemical reactions taken into account in the steam-reforming of methanol, according to the literature, are the following ones [151-154] ... 

Skeletal Cu-Zn catalysts show great potential as alternatives to coprecipitated Cu0-Zn0-Al203 catalysts used commercially for low temperature methanol synthesis and water gas shift (WGS) reactions. They can also be used for other reactions such as steam reforming of methanol, methyl formate production by dehydrogenation of methanol, and hydrogenolysis of alkyl formates to produce alcohols. In all these reactions zinc oxide-promoted skeletal copper catalysts have been found to have high activity and selectivity. 

Kniep BL, et al. Rational design of nanostructured copper-zinc oxide catalysts for the steam reforming of methanol. Angew Chem Int Ed. 2004 43(1) 112 15. 

Tsai MC, et al. Promotion of a copper-zinc catalyst with rare earth for the steam reforming of methanol at low temperatures. J Catal. 2011 279(2) 241—5. 

Matsumura Y, Ishibe H. High temperature steam reforming of methanol over Cu/ZnO/ Zr02 catalysts. Appl Catal B Environ 2009 91 (1 —2) 524—32. 

Jones SD, Hagelin-Weaver HE. Steam reforming of methanol over CeC>2- and ZrC>2-promoted Cu-ZnO catalysts supported on nanoparticle AI2O3. Appl Catal B Environ. 2009 90(l-2) 195-204. 

Velu S, Suzuki K. Selective production of hydrogen for fuel cells via oxidative steam reforming of methanol over CuZnAl oxide catalysts effect of substitution of zirconium and cerium on the catalytic performance. Top Catal. 2003 22(3-4) 235-44. 

Turco M, et al. Production of hydrogen from oxidative steam reforming of methanol -I. Preparation and characterization of Cu/ZnO/Al2C>3 catalysts from a hydrotalcite-like LDH precursor. J Catal. 2004 228(l) 43-55. 

Purnama H, et al. Activity and selectivity of a nanostructured Cu0/Zr02 catalyst in the steam reforming of methanol. Catal Lett. 2004 94(l-2) 61-8. 

Liu YY, et al. Highly active copper/ceria catalysts for steam reforming of methanol. Appl Catal A Gen. 2002 223(l-2) 137-45. 

Szizybalski A, et al. In situ investigations of structure-activity relationships of a Cu/Zr02 catalyst for the steam reforming of methanol. J Catal. 2005 233(2) 297-307. 

Frank B, et al. Steam reforming of methanol over copper-containing catalysts influence of support material on microkinetics. J Catal. 2007 246(l) 177-92. 

Goodby BE, Pemberton JE. XPS characterization of a commercial Cu/Zn0/Al203 catalyst - effects of oxidation, reduction, and the steam reformation of methanol. Appl Spectrosc. 1988 42(5) 754-60. 

Zhang XR, et al. A unique microwave effect on the microstructural modification of Cu/ZnO/Al2C>3 catalysts for steam reforming of methanol. Chem Commun. 2005(32) 4104-6. 

Wang LC, et al. Production of hydrogen by steam reforming of methanol over Cu/ZnO catalysts prepared via a practical soft reactive grinding route based on dry oxalate-precursor synthesis. J Catal. 2007 246(1) 193-204. 

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