Palladium-copper alloy membranes

Howard BH, Killmeyer RP, Rothenberger KS, Cugini AV, Morreale BD, Enick RM, and Bustamante F. Hydrogen performance of palladium-copper alloy membranes over a wide range of temperatures and pressures. J. Membr. Sci. 2004 241 207-218. 

The Effect of Continuous H2S Exposure on the Performance of Thick Palladium-Copper Alloy Membranes... 

Morreale, Bryan David. The influence of H2S on palladium and palladium-copper alloy membranes. Dissertation, University of Pittsburgh, Pittsburgh, P. A, August 2006, and references therein. 

Figure 5.4 Comparison of effects on a palladium-copper alloy membrane by thermal cycling (A) a Monel membrane support, (B) a 304 stainless steel membrane support.

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. 

Mishchenko, A. P., M. E. Sarylova, V. M. Gryaznov, V. S. Smirnov, N. R. Roshan, V. P. Polyakova and E. M. Savitskii. 1977. Hydrogen permeability and catalytic activity of membranes made of palladium-copper alloys in relation to the dehydrogenation of 1,2-cyclohexanediol. Izv. Akad. Nauk SSSR, Ser. Khim. 7 1620-1622. 

If a thinner membrane is required, then one must choose a supported membrane. The permselective metal layer may be palladium or, more commonly, palladium-silver alloy, palladium-copper alloy, or other alloy of palladium. The permselective layer ranges in thickness from about 2-25 /an thinner than 2/rm is very difficult to achieve without introducing pin holes and other adverse defects into the permselective layer. The support layer is porous and is composed of either metal (such as sintered stainless steel or tightly woven wire cloth) or an inert ceramic alumina is very common. Since all of the mechanical strength is derived from the support layer, consideration must be given to its shape and thickness. 

A. V. Enick, R. M., Effect of hydrogen-sulfide on the hydrogen permeance of palladium-copper alloys at elevated temperatures. Journal of Membrane Science 2004,241, (2), 219,... 

Juda W, Krueger CW, Bombard TR. Diffusion-bonded palladium-copper alloy framed membrane for pure hydrogen generators and the hke and method of preparing the same. US Patent 5904754,1999. 

Roa, F. and J.D. Way, Influence of alloy composition and membrane fabrication on the pressure dependence of the hydrogen flux of palladium-copper membranes, Ind. Eng. Chem. Res., 42(23),... 

Thus the palladium alloy with 53% copper proved to be more permeable than palladium [37]. However, the maximal operating temperature for membranes of this alloy is 623 K. Palladium-ruthenium alloys are more thermostable and may be used up to 823 K. At the increase in ruthenium content from 1 to 9.4 at.%, the hydrogen permeability of the alloys attained a maximum at a ruthenium content of about 4.5%. The long-term strength of this alloy at 823 K after service for lOOOhr was greater by a factor of almost 5 than that of pure palladium [35]. 

Juda W, Krueger CW, Bombard TR. Method of producing thin palladium-copper and the hke, palladium alloy membranes by solid-solid metallic interdifiusion, and improved membrane. US Patent 6238465,2001. 

Palladium-Copper and Palladium-Gold Alloy Composite Membranes for Hydrogen Separations... 

Palladium-Copper and PaUadium-Gold Alloy Composite Membranes... 

McKinley studied the effects of poisoning by H2S on membrane materials of pure palladium, and alloys of palladium with silver, nickel, copper and gold [74]. Only the Pd-Au alloys showed reasonable resistance to poisoning by hydrogen sulfide according to McKinley [74]. An alloy of 60 wt% Pd and 40 wt% Au retained 80% of its initial (unpoisoned) permeability upon exposure to 4 ppm H2S and retained 40% of its permeability during exposure to 20 ppm H2S at 623 K (350 °C). In contrast, pure palladium was poisoned to 30% of its initial, unpoisoned value after 6 days exposure to only 4 ppm H2S. An alloy of 73 wt% Pd and 27 wt% Ag was completely poisoned within hours after exposure to only 4 ppm... 

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