20 - Bioreactor and Enzymatic Reactions in Bioremediation

Abstract

Intellectual revolution with new visions and hopes is responsible for the development of membrane-associated bioreactor with specific emphasis on waste valorization. Generally, an enzyme or microorganism is immobilized in the matrix and is used in a membrane bioreactor. Conversely, a membrane separation unit is associated with a bioreactor to separate out a reaction product, known as catalytic membrane reactor. The performance of membrane-associated bioreactors is considerably influenced by the operating conditions, such as substrate concentration, immobilized matrix material, types of immobilization, and characteristics of the membrane module. The advantages of membrane-associated bioreactors over free-enzyme biochemical reactions and packed bed reactors are the large surface area of the immobilization matrix and better product recovery, along with heterogeneous reactions, reuse of enzymes, and continuous operation of the reactor. Moreover, due to possible separation of products and reactants, reversible reactions are always facilitated in this type of reactor. In the present chapter, the characteristics of membrane-associated bioreactors, more particularly membrane bioreactors with special interest of immobilization technology of enzyme and microorganism, hydrodynamic study associated with chemical reactions, and its application is described. Furthermore the application of membrane bioreactor with respect to synthesis of prebiotic galactooligosaccharide, and lactic acid have been elucidated.