Nanostructured metal–carbon membrane catalysts based on carbonized PAN
The nanostructured catalytic membranes consisted of stainless steel porous support modified with carbon layer, and catalytic layer, containing Pt–Ru alloy nanoparticles, homogeneously dispersed in carbon matrix, were synthesized for the first time by IR-pyrolysis method. The optimization of pore size of plates of porous stainless steel was carried out using carbon, prepared by IR-pyrolysis of PAN, introduced in support pores in DMFA solution. The structure and thickness of modifying layer were controlled by PAN initial concentration and IR-annealing intensity. The selectivity of helium–argon pair separation increased monotonously as carbon layer thickness increased. The catalytic layers, based on IR-PAN carbon, Pt–Ru nanoparticles and finely dispersed activated carbon SKT or detonation nanodiamonds, were deposited on carbon modified porous membranes. The selectivity of permeability for pair helium–argon increased after catalytic layer deposition, becoming equal to the ideal Knudsen value. Cyclohexane dehydrogenation on obtained composite metal–carbon membrane catalysts were carried out in plug flow catalytic membrane reactor at the temperatures from 220 to 520 °C. The productivity on the unit of mass of active metal of composite membrane metal–carbon catalyst, was shown to be significantly higher than that of the same metal–carbon composites in grained form.
Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (203 K)Download as PowerPoint slideHighlights► We prepared membrane containing Pt–Ru nanoparticles dispersed in carbon matrix firstly. ► The selectivity of permeability is in accordance with Knudsen diffusive law. ► The productivity of the membrane is higher than that of the same composite in grained form.
Journal: Catalysis Today - Volume 186, Issue 1, 1 June 2012, Pages 7–11