ABSTRACT
Catalytic phenomena affect virtually all aspects of our lives: enzymatic catalysis, for example, constitutes the basis for most of the biochemistry associated with life, and about 80% of industrial chemical processes are concerned with at least one catalytic reaction. Biopolymers offer a wide resource in terms of both the quantities annually produced and the diversity of functional groups available for interactions with solutes. Polysaccharide-based materials and protein-based materials are the biopolymers most frequently cited for the preparation of heterogeneous catalysts. Amine groups of chitosan react with aldehyde functions of the cross-linking agent through the so-called Schiff base reaction. Alginate is another example of a polysaccharide mainly produced from marine resources. Cellulose and starch are very similar materials in terms of structural units; each of them is constituted by glucopyranose units. Gelatin is prepared by the thermal degeneration of collagen, which is usually isolated from animal skin and bones and fish skin by weak acidic treatment.
