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Grafting of aminated oligogalacturonans onto Douglas fir barks. A new route for the enhancement of their lead (II) binding capacities

Laboratoire de Chimie des Substances Naturelles, EA1069, Faculté des Sciences et Techniques, 123 avenue Albert Thomas, F-87060 Limoges, France.
Journal of hazardous materials (Impact Factor: 4.53). 10/2010; 182(1-3):279-85. DOI: 10.1016/j.jhazmat.2010.06.027
Source: PubMed

ABSTRACT

Chemical modification of Douglas fir bark and its subsequent utilization in adsorption of PbII from aqueous solutions was investigated. A new approach to enhance the natural properties of bark by covalent grafting of oligogalacturonans was developed. The polysaccharidic moiety of barks was functionalized by periodate oxidation and derivatized after reductive amination in presence of aminated oligogalacturonic acid. PbII adsorption isotherms of derivatized barks were then determined and compared with the capabilities of crude barks using the Langmuir adsorption model in terms of affinity (b) and maximum binding capacities (q(max)). Derivatization resulted in significant enhancements of the q(max) values (up to x8), along with little change of the affinity parameter.

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