Supported Pd-Au Membrane Reactor for Hydrogen Production: Membrane Preparation, Characterization and Testing

Abstract

A supported Pd-Au (Au 7wt%) membrane was produced by electroless plating deposition. Permeation tests were performed with pure gas (H 2 , H 2 , N 2 , CO 2 , CH 4 ) for long time operation. After around 400 h under testing, the composite Pd-Au membrane achieved steady state condition, with an H 2 /N 2 ideal selectivity of around 500 at 420 °C and 50 kPa as transmembrane pressure, remaining stable up to 1100 h under operation. Afterwards, the membrane was allocated in a membrane reactor module for methane steam reforming reaction tests. As a preliminary application, at 420 °C, 300 kPa of reaction pressure, space velocity of 4100 h −1 , 40% methane conversion and 35% hydrogen recovery were reached using a commercial Ni/Al 2 O 3 catalyst. Unfortunately, a severe coke deposition affected irreversibly the composite membrane, determining the loss of the hydrogen permeation characteristics of the supported Pd-Au membrane.

Effect of Au addition on hydrogen permeation and the resistance to H2S on Pd-Ag alloy membranes

“…(M1Au) (Figure 4b), showing that the permeation characteristics of the composite membrane follows a slightly different permeation mechanism than the Sieverts-Fick [7]. This behavior has also been found by Iulianelli et al [27] for a PdAu 7 dense layer supported on a porous stainless steel (PSS) support at 420 °C. However, Pd 94.9 Ag 5.1 (M1) as depicted in Figure 4a, showed its highest regression factor with n = 0.5 in the range 400-500 °C and with n = 0.6 at 550 °C and 600 °C, confirming that the addition of Au leads to an increasing importance of adsorption dissociation as rate limiting step instead of bulk transport in the solution-diffusion model for hydrogen permeation.…”

Interlayer Properties of In-Situ Oxidized Porous Stainless Steel for Preparation of Composite Pd Membranes

“…They ensure that the thickness of this intermediate layer was not enough to facilitate the generation of a thin palladium layer in a comparable grade to other alternatives but its presence had a negative effect on the permeate flow rate. More recently, Iulianelli et al [52] also oxidized tubular PSS supports prior to incorporate a PdAu thin film by electroless plating. In this case, the support was oxidized for 12 h at a relatively low temperature (500 • C) and additionally modified with pre-activated alumina particles.…”

Glycerol Production and Transformation: A Critical Review with Particular Emphasis on Glycerol Reforming Reaction for Producing Hydrogen in Conventional and Membrane Reactors

“…However, glycerol can be further used for producing H 2 via steam reforming, partial oxidation and pyrolysis reactions [93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,…”