Catalyst coated membrane technology

Membrane Reactor. Another area of current activity uses membranes in ethane dehydrogenation to shift the ethane to ethylene equiUbrium. The use of membranes is not new, and has been used in many separation processes. However, these membranes, which are mostly biomembranes, are not suitable for dehydrogenation reactions that require high temperatures. Technology has improved to produce ceramic and other inorganic (90) membranes that can be used at high temperatures (600°C and above). In addition, the suitable catalysts can be coated without blocking the pores of the membrane. Therefore, catalyst-coated membranes can be used for reaction and separation. 

M. K. Debe. Novel catalysts, catalyst supports and catalyst coated membrane methods. In Handbook of fuel cells Fundamentals, technology and applications. Vol. 3 Fuel cell technology and applications, ed. W. Vielstich, H. A. Gasteiger, and A. Lamm, 576 (2003). New York John Wiley Sons. 

Debe, M., Novel catalysts, catalysts support and catalysts coated membrane methods, in Elandbook of Fuel Cells Fundamentals, Technology, and Applications, 1st ed., Vielstich, W., Lamm, A., and Gasteiger, H.A., Eds., John Wiley Sons, West Sussex, England, 2003, p. 576. 

Debe M (2003) Novel Catalysts, Catalyst Supports and Catalysts Coated Membrane Methods. In Vielstich W, Gasteiger HA, Lamm A (eds) Handbook of Fuel Cells -Fimdamentals, Technology and Application, Part 3. John Wiley Sons, Chichester, p 576... 

Wuhan University of Technology A Chinese key state university with a total student enrollment of more than 52,700. It was established in 2000 by combining three local universities. Wuhan University of Technology is a leading Chinese university in developing catalyst-coated membranes (CCMs) for PEMFCs. It is located in Wuhan, Hubei, China. University website http //www.whut.edu.cn. 

Debe MK (2003) Novel catalysts, catalyst support and catalyst coated membrane methods. In Vielstich MW, Lamm A, Gasteiger HA (eds) Handbook of fuel cells-fundamentals, technology and applications, vol 3. Wiley, New York, Chapter 45... 

Work at the Jet Propulsion Laboratory (California Institute of Technology) and University of South California, Los Angeles, demonstrated for the first time the power output capability of a DMFC equipped with PEM [52]. From fliis work. Figure 4.2(a) shows flic improved polarization performance of flic PtRu/C anode with Nafion 117 electrolyte compared to 0.5 M H2SO4, whilst Figure 4.2(b) exemplifies the fuel cell performance with the catalyst coated membrane. 

M. K. Debe Novel catalysts, catalysts support and catalysts coated membrane methods , in W. Vielstich, A. Lamm, H. Gasteiger (Eds.), Handbook of Fuel Cells -Fundamentals, Technology and Applications, Chapter 45, Vol. 3, Wiley, UK, 2003. ... 

The technology just described, of applying catalysts to the diffusion layers and then hot-pressing all components, results in a catalyst-coated diffusion layer (CCDL). Another technology, which results in a catalyst-coated membrane (CCM), involves all components of the catalytic layer being evaporated as a Ihin layer directly onto the membrane. 

Barbieri et al. [146] developed a MR for the WGS reaction. A palladium/silver fihn containing 23 wL% silver, which had a thickness between 1 and 1.5 pm, v is prepared by sputtering and coated onto a porous stainless steel support. This preparation method generated a much higher ratio of pore size to fihn thickness compared to conventional methods. Tubular membranes of 13 mm outer diameter, 10 to 20 mm length, were fabricated. Commercial Cu-based catalyst from Haldor-Topsoe was introduced into the fixed bed. At reaction temperatures between 260 and 300 C, and a GHSV of 2085 h, the thermodynamic equilibrium conversion could be exceeded by 5-10% by the membrane technology. 

Table 6.2 Advances in membrane cell technology for the chlor-alkali industry. The first cells had a cation-permeable membrane made from a sulfonate polymer resin, catalyst-coated anodes, and steel cathodes.

Process intensification and inorganic synthesis - including micro-reactor technology, membrane reactors sand catalyst coating. 

Cleghorn, S.J.C., Kolde, J., Liu, W. 2003. Catalyst coated composites membranes, in Handbook of Fuel Cells—Fundamentals, Technology and Applications, eds. W. 4elstich, H.A. Gasteiger, and A. Lamm. Chichester, U.K. John Mley Sons. 

Cleghorn S, Kolde J and Liu W (2(X)3) Catalyst coated composite membranes Volume 3, Part 3, pp. 566-575. Handbook of Fuel Cells—Fundamentals, Technology and Applications, edited by Wolf Vielstich, Arnold Lamm, Hubert A. Gasteiger, John Wiley Sons Ltd, Chichester, 2(X)3. 

Reetz et al.59 have introduced polypropylenimine (PPI) dendrimers as the core for building phosphine-coated constructs that can complex with Rh(COD) BF4, where COD = 1,5-cyclooctadiene, to instill the desired catalytic character. Hydroformylation of 1-octene with these metallodendrimers was shown to have turnover numbers that were comparable to those of monomeric analogs. It was pointed out that these catalysts could be easily recovered by means of membrane separation technology.60 Gong et al. have used water-soluble, phosphonated dendritic... 

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