Nanostructured Palladium-Doped Silica Membrane Layer Synthesis for Hydrogen Separation: Effect of Activated Sublayers

Document Type : Research Paper


1 Nanostructure Material Research Center, Sahand University of Technology, Tabriz, Iran

2 Nanostructure Materials Research Center (NMRC)

3 Nanostructure Material Research Center (NMRC), Sahand University of Technology


Palladium doped silica membranes were synthesized by the sol-gel method using two different procedures. The first palladium-doped silica membrane (M1) was synthesized with a coating of four layers of silica-palladium sol. The second membrane (M2) was synthesized with a coating of two silica layers followed by a coating of two silica-palladium layers. Scanning electron microscopy (SEM) proved the formation of uniform γ-alumina interlayers on the supports. SEM results for M1 showed that  synthesis of a membrane with this procedure leads to the formation of crack on the membrane selective layer. Single gas permeation measurements of H2 and N2 were carried out at room temperature, 100 °C and 550 °C. Gas permeation results revealed that Knudsen diffusion was dominant in permeation of these gases through membrane M1 while the dominant mechanism in permeation of gases through  membrane M2 was activated transport which has exhibited different behavior in comparison with M1. This result is due to the activated sublayers of membrane M2. In this case, H2 permeance increases and N2 permeance decreases with increasing temperature, leading to better separation perforamce of membrane M2 over M1 in separation of H2. Therefore, using the activated silica sublayer in the synthesis of M2 can be used as a high potential method to synthesize a selective palladium-doped silica membrane.


Main Subjects

[1] Adhikari S. and Fernando S. "Hydrogen Membrane Separation Techniques", Industrial & Engineering Chemistry Research, 2006, 45: 875.
[2] Battersby S., Smart S., Ladewig B., Liu Sh., Duke M., Rudolph V. and Costa C. D. "Hydrothermal stability of cobalt silica membranes in a water gas shift membrane reactor". Separation and Purification Technology, 2009, 66: 299.
[3]  Yang J., Fan W. and Bell C. “Effect of calcination atmosphere on microstructure and H2/CO2 separation of palladium-doped silica membranes”, Separation and Purification Technology, 2019: Accepted Manuscript.
[4]  Uhlmann D., Liu Sh., Ladewig B. and Costa C. D. "Cobalt-doped silica membranes for gas separation". Journal of Membrane Science, 2009, 326: 316.
[5]  Li G., Kanezashi M. and Tsuru T. "Preparation of organic–inorganic hybrid silica membranes using organoalkoxysilanes: The effect of pendant groups". Journal of Membrane Science, 2011, 379: 287.
[6]   Battersby S., Tasaki T., Smart S., Ladewig B., Liu Sh., Duke M., Rudolph V. and Costa C. D.   "Performance of cobalt silica membranes in gas mixture separation". Journal of membrane science, 2011, 329: 91.
[7]  Burgraff A. J. and Cot L. “Fundamental of Inorganic Membrane Science and Technology”. Membranes Science and Technology Series, Elsevier, Amesterdam, 1996:4.
[8]  Ayral A., Julbe A., Rouessac V., Roualdes S. and Durand J. “Microporous Silica Membranes – Basic Principles and Recent Advances”. Membrane Science and Technology, 2008, 13: 33-79.
[9]  Igi R., Yoshioka T., Ikuhara Y. H., Iwamoto Y. and Tsuru T. "Characterization of Co-Doped Silica for Improved Hydrothermal Stability and Application to Hydrogen Separation Membranes at High Temperatures". Journal of American Ceramic Society, 2008, 91: 2975.
[10]  Ballinger B., Motuzas J., Smart S. and Costa C. D. "Palladium cobalt binary doping of molecular sieving silica membranes", Journal of Membrane Science, 2014, 451: 185.
[11]  Kanezashi M., Sano M., Yoshioka T. and Tsuru T. "Extremely thin Pd–silica mixed matrix membranes with nano-dispersion for improved hydrogen permeability". Chemical Communications, 2010, 46: 6171.
[12]  Kanezashi M. and Asaeda M. "Hydrogen permeation characteristics and stability of Ni-doped silica membranes in steam at high temperature". Journal of Membrane Science, 2006, 271: 86.
[13]  Smart S., Vente J. F. and Costa C. D.  "High temperature H2/CO2 separation using cobalt oxide silica membranes". International Journal of Hydrogen Energy, 2012, 37: 12700.
[14]  Lee D., Yu Ch. and Lee K. "Synthesis of Pd particle-deposited microporous silica membranes via a vacuum-impregnation method and their gas permeation behavior". Journal of Colloid and Interface Science, 2008, 325: 447.
[15]  Kanezashi M., Fuchigami D., Yoshioka T. and Tsuru T. "Control of Pd dispersion in sol–gel-derived amorphous silica membranes for hydrogen separation at high temperatures". Journal of Membrane Science, 2013, 439: 78.
[16]  Jabbari A., Ghasemzadeh K., Khajavi P., Assa F., Abdi M. A., Babaluo A. A. and Basile A. "Surface modification of alpha-alumina support in synthesis of silica membrane for hydrogen purification". International Journal of Hydrogen Energy, 2014, 39: 18585.
[17]  Uhlhorn R., Keizer K. and Burggraaf A."Synthesis of ceramic membranes part I synthesis of non-supported and supported γ-alumina membranes without defects". Journal of Material Science, 1992, 27: 527-537.
[18]  Mohammadi Z., Rafia N. and Babaluo A. A. "Microporous silica membranes for hydrogen separation". Proceeding of the 9th International Chemical Engineering Congress & Exhibition, Shiraz, December, 2015: 26.
[19]  Tsai C., Tam S., Lu Y. and Brinker C. “Dual-layer asymmetric microporous silica membranes”. Journal of Membrane Science, 2000, 169: 255–268.
[20]  Ballinger B., Motuzas J., Smart S. and Costa J. “Palladium cobalt binary doping of molecular sieving silica membranes”, Membrane Sciene and Technology, 2014, 451: 185-191.
[21]  A. Darmawan, ., Motuzas J., Smart S., A. Julbe A. and Costa J. “Binary iron cobalt oxide silica membrane for gas separation”, Journal of Membrane Science, 2015, 474: 32-38.
[22]  Ballinger B., Motuzas J., Smart S. and Costa J. “Gas permeation redox effecton binary lanthanum cobalt silica Membranes with enhanced silicate formation”, Journal of Membrane Science, 2015, 489: 220-226.
[23] Yang J., Fan W. Hou H., Guo Y. Jia D. and Xing X. “Effect of DMF addition on the phase-chemical structure of Pd-doped methyl-modified silica membrane materials calcined in air atmosphere”, Ferroelectrics, 2018, 528: 83-89.