2024-03-28T18:00:33Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1886362020-12-11T10:14:02Zcom_10261_89com_10261_3col_10261_342
High-temperature stability of Pd alloy membranes containing Cu and Au
Jia, Haiyuan
Wu, Ping
Zeng, Gaofeng
Salas, Eduardo
Serrano Rubio, Aída
Castro, Germán R.
Xu, Hengyong
Sun, Chenglin
Goldbach, Andreas
Chinese Academy of Sciences
Helmholtz Association
National Natural Science Foundation of China
Ministerio de Economía y Competitividad (España)
Consejo Superior de Investigaciones Científicas (España)
Ternary Pd alloy membrane
Alloy segregation
High-temperature stability
PdAu membrane
PdCu membrane
High-temperature stability of Pd-based membranes benefits their application in steam reformers and sulfur-contaminated H streams because both membrane reforming efficiency and sulfur tolerance of Pd alloys increase much with temperature. Hence, we investigated PdCu, PdAu, and PdCuAu membranes supported on porous ceramic tubes between 500 °C and 650 °C. Remarkably, PdCu membranes were much more stable than Au-containing ones. The H permeation rates of some PdAu and PdCuAu membranes declined at 550 °C with substantially increasing N fluxes. This was triggered by severe morphological deformation of the Au alloy films into stoichiometrically inhomogeneous, cavernous structures. The H fluxes of the PdCu membranes started to decline at 650 °C with leak flows increasing slightly. Moreover, the PdCu layer morphology remained dense and compositionally homogeneous even after testing for up to 4800 h between 500 and 650 °C. The strikingly different high-temperature stability can be understood by considering the divergent surface segregation tendencies of Cu and Au and their differing impact on hydrogen solubility in Pd alloys. As a result, Au may desorb much more easily from membranes than Cu leading to structural instability above 500 °C during operation in H. The instability of PdAu membranes at high temperatures may be mitigated by addition of sufficient Cu to obtain ternary membranes with good H permeability and better thermal stability.
2019-08-20T12:07:24Z
2019-08-20T12:07:24Z
2017-12-15
2019-08-20T12:07:25Z
artículo
Journal of Membrane Science 544: 151-160 (2017)
http://hdl.handle.net/10261/188636
10.1016/j.memsci.2017.09.012
http://dx.doi.org/10.13039/501100001809
http://dx.doi.org/10.13039/501100003329
http://dx.doi.org/10.13039/501100003339
http://dx.doi.org/10.13039/501100002367
http://dx.doi.org/10.13039/501100001656
eng
https://doi.org/10.1016/j.memsci.2017.09.012
Sí
closedAccess
Elsevier