Alloy membrane reactors

Barbieri, G., Scura, F. and Brunetti, A. (2008) Mathematical modelling ofPd-alloy membrane reactors, in Inorganic Membranes Synthesis, Characterization and Applications, vol. 13 (eds R. Mallada and M. Menendez), Membrane Science and Technology, Elsevier BV, Chapter 9 (ISSN... 

Marigliano, G., Barbieri, G. and Drioli, E. (2003) Equilibrium conversion for a Pd-alloy membrane reactor. Dependence on the temperature and pressure. Chemical Engineering and Processing, 42 (3), 231-236. 

Thermodynamic Equilibrium in Pd-Alloy Membrane Reactor 301 Conclusions 303 References 306... 

Gryaznov ct al. [30-32] have done pioneering work in the study of differently designed palladium-alloy membrane reactors for reactions in both gas phase and liquid phase. Most interest was directed to the composition and properties of the membranes, which were decisive questions at this stage of the development, and still are. Selectivity problems in various organic chemical reactions were also of importance to study. 

Zhang X, Xiong G, and Yang W, Hydrogen separation from the mixtures in a thin Pd-Cu alloy membrane reactor. Stud. Surf. Sci. Catal. 2007 167(Natural Gas Conversion VIII) 219-224. 

Conventional production of vitamin K consists of four steps hydrogenation of 2-methylnaphthoquinone-l,4 to 2-methylnaphthohydroquinone-l,4 in a solvent in the presence of Raney nickel separation of the product from the catalyst by filtration evaporation of the solvent and boiling with acetic anhydride. Because the anhydride is highly corrosive, it tends to attack the nickel, and hence complete separation of the catalyst is necessary. On the other hand, use of a palladium alloy membrane reactor eliminates corrosion and makes it possible to complete the whole process in a single step (Gryaznov et al., 1986). The overall reaction is... 

Miyamoto, M., Hayakawa, C., Kamata, K. et al. (2011) Influence of the pre-reformer in steam reforming of dodecane using a Pd alloy membrane reactor. International Journal of Hydrogen Energy, 36, 7771-7775. 

Enick, R., Bustamante, F., lyoha, O., Howard, B., Killmeyer, R., Morreale, B., et al. (2004). Conducting the homogenous water-gas shift reaction in a palladium-copper alloy membrane reactor at high temperature and pressure. NETL report. 

In addition, the filament reactor can contain a membrane-separation function by grouping threads of filaments around an inner empty reactor core, that guides the permeate and may also increase permeation by reaction. Thus, the tube reactor constructed in such a way comprises two concentric zones, separated by a permeable Pd/Ag alloy membrane in the form of a tube. The reaction takes place in the filament zone. One product such as hydrogen is removed via the membrane and... 

Because Pd-alloy membranes operate at high temperatures in the range of WGS reaction and on the lower end of methane reforming reaction, they can be used in a membrane reactor configuration for the simultaneous separation of hydrogen. As discussed earlier,... 

An integrated proof-of-concept (POC) size fluidized-bed methane reformer with embedded palladium membrane modules for simultaneous hydrogen separation is being developed for demonstration (Tamhankar et al., 2007). The membrane modules will use two 6 in. X 11 in. Pd-alloy membrane foils, 25-pm thick, supported on a porous support. The developmental fluidized-bed reactor will house a total of five (5) membrane modules with a total membrane area of about 0.43 m2 and is scheduled for demonstration by September 2007. 

Damle, A.S., J. Schwartz, and P. Apte, Palladium-alloy based Membrane Reactor Process for Hydrogen Generation, Proceedings of2005 Fuel Cell Seminar, Palm Springs, CA, November 2005. 

V-Ti-Ni alloys and Fe- /Co-Based metallic glasses have been evaluated with respect to hydrogen permeability for potential use in hydrogen purification membrane reactor application. Microstructural characterization of the V-Ti-Ni alloy using SEM has shown similar microstructural features to a previously evaluated Nb-Ti-Ni alloy namely, the occurrence of a primary phase surrounded by interdendritic eutectic. 

The next step in the processor development will be to integrate the palladium alloy membrane with the methanol steam reformer reactor. The researchers anticipate that the addition of the palladium membrane will improve the reactor performance due to in-situ hydrogen removal. 

The feasibility of the palladium membrane system with an oxidation reaction on the permeation side and 1-butene dehydrogenation reaction on the reaction side in a membrane reactor has been successfully demonstrated. The palladium and its alloy membrane not only can withstand high temperature but also are selectively permeable to hydrogen... 

V. M. Gryaznov and his co-workers (e.g. IGryaznov, 1986]) have extensively explored the permselective properties of palladium and its alloys as dense membranes and membrane reactors. While their studies will be discussed in later chapters, it suffices to say that the palladium-based membranes have reached the verge of a commercialization potential for the process industry. 

Palladium and selective alloys with other metals can be fabricated into dense membrane reactors in foil or tubular form, mostly in thin layers to reduce permeation resistance. In... 

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