Title : Extraction of collagen from chicken waste and development of cellulose nanofiber-reinforced hydrogels for the hexavalent chromium metal adsorption from wastewater: Optimization and characterization
Abstract:
This study was conducted by extracting collagen from broiler skin tissue and cellulose nanofibers (CNFs) from bacterial cellulose to fabricate collagen-only (Col-H) and collagen/CNF composite (Col/CNF-H) hydrogels to optimize their performance for Cr (VI) adsorption. Collagen was obtained via sequential alkali deproteinization, defatting, and acid solubilization, while CNFs were produced from bacterial cellulose using the acid hydrolysis method. Hydrogels were formed at a pH of 7.4 and a temperature of 37 °C using a collagen solution (18.5 mg/mL), with composites prepared by mixing collagen with a 5 % CNF suspension. CNF incorporation significantly accelerated gelation, improved water retention (p < 0.01), and increased swelling of the composite hydrogel. FTIR spectra verified combined collagen-cellulose signatures and an amide II shift to 1556 cm?¹, indicating interfacial interactions between the polymers. A denser, more interconnected fibrillar network was shown by CLSM and SEM. In batch adsorption tests, adsorption increased from 3.2 ± 0.1 mg/g (Col-H) to a synergistic 8.0 ± 0.2 mg/g for Col/CNF-H. Overall, Col/CNF-H presents a low-cost solution for Cr (VI) removal and requires scale-up and validation in real wastewater systems.
