Adsorbed “membrane

Figure 2. Responses of the DOPH adsorbed membrane to five basic taste substances. The membrane potential is taken as relative.

Figure 3. Surface structures of the DOPH adsorbed membrane treated with 100 mM MSG (a), 1 mM IMP (b) and 100 mM MSG+1 mM IMP (c).

Two novel hybrid concepts for gas separation using adsorption technology have emerged in recent years. They include (a) adsorbent membranes, and (b) simultaneous adsorption and reaction. 

Avramescu ME, Girones M, Bomeman Z, and Wessling M. Preparation of mixed matrix adsorber membranes for protein recovery. J. Membr. Sci. 2003 218 219-233. 

Pores, and espjecially mesopores and micropores, play an essential role in physical and chemical properties of industrially important materials like adsorbents, membranes, catalysts etc. The description of transport phenomena in porous materials has received attention due to its importance in many applications such as drying, moisture transport in building materials, filtration etc. Although widely different, these applications present many similarities since they all depend on the same type of transport phenomena occurring in a porous media environment. In particular, transport in mesoporous media and the associated phenomena of multilayer adsorption and capillary condensation have been investigated as a separation mechanism for gas mixtures. 

Other recent ideas on (i) simultaneous sorption-reaction process concepts using the principles of a novel PSA technology for the production of fuel cell-grade hydrogen and (ii) improving the H2 recovery from existing H2 PSA processes by integrating it with additional PSA units or nanoporous SSF adsorbent membrane systems are reviewed. 

Adsorption on glass fiber filters is simple, inexpensive, and popular. The large internal surface of the filters adsorbs membrane vesicles via weak electrostatic and hydrophobic interactions. Bigger vesicles (mitochondriae, synaptosomes) are also filtered mechanically (pore size of glass fiber filters 1 to 3 pm 0 mitochondriae 1 pm). Molecules in solution largely... 

Disadvantages of the known porous polymeric membrane preparation processes are that they involve additional process steps after the formation of the fiber to come to a final product. It is therefore desirable to have a more efficient preparation process. A new method to prepare structures of any geometry (Figure 6.13c through f) and large variety of functionality was recently proposed [61]. The authors proposed to incorporate the functionality by dispersion of particles in a polymeric porous structure formed by phase inversion. A slurry of dissolved polymer and particulate material can be cast as a flat film or spun into a fiber and then solidified by a phase inversion process. This concept is nowadays commercialized by Mosaic Systems. The adsorber membranes prepared via this route contain particles tightly held together within a polymeric matrix of different shapes, which can be operated either in stack of microporous flat membranes or as a bundle of solid or hollow-fiber membranes. 

In industry, separations effected by porous solid materials (adsorbents, membranes, ion exchange resins, special kinds of solid matrices) are seldom applied in comparison to separations carried out in systems with fluid phases. The reason may be a poorer state of the art than in fluid systems. Furthermore, the handling of flitid systems is much easier than the handling of systems with solid phases. On the other... 

Pharmaceuticals, cosmetics, inks, paints, foods, lubrication, food products, dyestuffs, foams, agriculture chemicals Photographic products, ceramics, paper coatings, magnetic media, catalysts, chromatographic adsorbents, membrane and latex film, electrophotographic toners... 

---