Abstract

For the immobilization of micro-organisms and animal cells, in particular for anaerobic processes, such as the purification of waste water or for the biotechnological production of nutrition-essential or pharmacological substances, porous, sintered bodies are employed (inorganic carrier bodies). In particular, sintered glass in the form of Raschig rings with a double-pore structure, are employed. They have porosity-determining through-going macropores that permit a free exchange of fluid and gas from the interior of the carrier to the surroundings, and open micropores within the macropore walls, the diameter of the micropores being of the same order of magnitude as the size of the micro-organisms or cells. These carrier bodies typically have an open pore volume of 35% to 85%, 20% to 80% being accounted for by the macropores having a diameter of 20 to 500 μm, and 5%-50% by micropores having a diameter of 1-10 μm. These bodies are obtained by sintering a powder mixture comprising fine-grain material and a coarse-grain substance melting at a higher-than-sintering temperature and separable from the sintered product by allowing the latter to cool and separating (dissolving) out the soluble component.

Other References

• Durand et al., Process Biochemistry, Sep., 1978, pp. 14-23
• Huysman et al., "Factors Affecting the Colonization of Non Porous and Porous Packing Materials in Model Upflow Methane Reactors", Biotechnology Letters, vol. 5, No. 9, pp. 643-648 (1983