Sintered metal fibers catalyst

FIGURE 7 Schematic illustration of a sandwich reactor (top) and scanning electron microscopic images of a sintered metal fiber catalyst. 

M. Grasemarm, N. Semagina, A. Renken, L. Kiwi-Minsker, Hydrodynamics of a bubble column reactor staged with sintered metal fiber catalyst for contiuous 3-phase hydrogenation, Ind. ling. Chem. Res. 46 (2007) 8602. 

Figure 11.19 Staged bubble column reactor with integrated structured catalyst layers and microheat exchanger (a) vertical cut through the heat exchanger element (b) and sintered metal fiber catalyst (c) [53]. (Adapted with permission from Elsevier.)...

As an alternative to foams, fibrous materials in the form of tissues or filters may be used as structured catalysts [53,62-65]. Of particular interest for MSRs are sintered metal fibers (SMFs) [64,65]. These materials have open and homogeneous structures with porosities of 70-90% and high thermal conductivities, which ensure homogeneous temperatures in the catalytic bed. SMF materials consist of thin metallic fibers of 10-20 pm diameter. The small fiber diameters ensure high external fluid-solid mass transfer [66]. The fibers can be covered with a homogeneous layer of zeolitic material [66] or a washcoat, which can be impregnated with an active material [67,68]. Luther et al. [67] integrated the SMF catalyst in a... 

N. Semagina, M. Grasemann, N. Xanthopoulos, A. Renken, L. Kiwi-Minsker, Structured catalyst of Pd/ZnO on sintered metal fibers for 2-methyl-3-butyn-2-ol selective hydrogenation, J. Catal. 251 (2007) 213. 

Figure 6.6 (a) Schematic presentation of a "sandwich" reactor and (b) SEM images of sintered metal fiber (SMF) catalyst. (Reproduced from Ref. [22]. Copyright 2008, John Wiley Sons.)... 

Yuranov, I., Renken, A., and Kiwi-Minsker, L. (2005) Zeolite/sintered metal fibers composites as effective multi-structured catalysts. Appl. Catal,... 

Catalyst bodies can also be made of knitted threads or woven in fabrics, felts, etc. (5-7) (Figure 5). A wide variety of materials have been considered for such catalysfs, buf mosf affenfion has been given to glass, sintered metal, and carbon fibers. 

Although more expensive than melt fiberization, the sol processes offer advantages in fiber chemistry selection. In melt fiberization, viscosity and surface tension are gready influenced by additions of small quantities metallic oxides. In the sol process, where viscosity can be controlled independently, any number of metal salts may be added without adverse effects. These salts can serve as grain growth inhibitors, sintering aids, phase stabilizers, or catalysts. 

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