الفهرس | Only 14 pages are availabe for public view |
Abstract Radiation grafting of polysaccharides as (Starch, Pectin) with acrylic acid (AAc) and nano-materials as Cellulose nanofibers (CNF) were carried out using gamma irradiation for the preparation of naturally based nanocomposites hydrogels namely Starch-g-PAAc/CNF and Pectin-g- PAAc/CNF for removing Lead ions from wastewater. The best polymer/monomer composition of Starch: AAc is (4:1 v/v), and for Pectin: AAc is (3:2 v/v). The optimum irradiation dose is 20 kGy. Maximum swelling capability (by non-Fickian diffusion mechanism) was at pH 10, and at CNF content (0.1 g). Different investigation tools were used to characterized the morphology of the prepared nanocomposites like FTIR, SEM, TGA, XRD, TEM, and AFM, which reveals the rod- fibers nanostructure of CNF. The removal percentage of Pb (II) depends on the concentration of metal ions, temperature and time. The maximum removal percentage of Pb (II) was attained by Starch-g-PAA/CNF 0.1 and Pectin-g-PAAc/CNF0.1 (97% and 86.5% respectively). The biodegradability percent of the Starch-g-PAAc hydrogel in burial soil over 16 weeks exhibited (85%) and (74%) for Pectin-g-PAAc compared with the synthetic PAAc (55%). The bioremediation percent of the Starch-g-PAAc hydrogel in Nile River model wastewater over 4 weeks exhibited (56%) and for Pectin-g-PAAc (50%) compared with the synthetic PAAc (26%). The prepared biodegradable nanocomposites can be used as ecofriendly and environmentally adsorpents for the removal of heavy metals ions . |