Supports ceramic multichannel

In the early 1980s, former employees of Euroceral founded a small company located near Montpellier in France known as Ceram-Filtre. The rather less well-known Ceram-Filtre membranes comprise a multichannel support with 19 channels of 4 mm diameter and a microfiltration membrane made of an oxide. 

Some catalyst supports rely on a relatively low surface area stmctural member coated with a layer of a higher surface area support material. The automotive catalytic converter monolith support is an example of this technology. In this appHcation, a central core of multichanneled, low surface area, extmded ceramic about 10 cm in diameter is coated with high surface area partially hydrated alumina onto which are deposited small amounts of precious metals as the active catalytic species. 

To illustrate the functionality of the system a validation library was prepared and introduced into the reactor system. With the goal of achieving an optimal fluid distribution with a minimal pressure drop over the 96 reactor channels we used multichannel ceramic bodies ( miniliths ) as supports, which are impregnated with the corresponding catalyst precursor solutions in an automatic manner (for suitable technical solutions see Section 2). At each of the 96 reactor positions, a candidate material modified by impregnation is available for testing. The shadowed scheme... 

Honeycomb multichannel ceramic membranes on micro-porous cordierite support... 

Most inorganic membrane supports exhibit a tubular shape. This is a well-adapted geometry for cross-flow filtration in which the feed stream is circulated across the surface of the membrane and the permeated flux passes through the membrane in a perpendicular direction. Stainless steel, carbon, and ceramic are the most frequently used materials in the preparation of supports. As shown in Fig. 2, tubes or multichannel substrates can act as membrane supports. A well-designed support must be mechanically strong, and its resistance to fluid flow must be very low. Aiming at enhancing flux performances, multilayered substrates have been prepared that exhibit an asymmetric structure... 

Figure 7-15, Multichannel geometry of a, ceramic macroporous membrane coated at the surface of an alumina support by the slip-casting method.

Commercialized ceramic membranes can be of different configurations, from disc/fiat-sheet to multichannel tubes. The membrane microstructure is always very similar, that is, a thin separation layer made of finer particles supported onto a more porous multilayer substrate with a gradient pore structure, as shown in Figure 10.1. The only layer involved in separation is normally the thinnest layer with the finest pore size. The thickest layer, which consists of big particles for low resistance to permeates, provides the mechanical strength, whereas the layers in between are needed for a uniform formation of the top separation layer. Normally, different techniques are used for each individual layer, which results in soaring expenditures with the number of layers involved. 

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