Nanocellulose fibers for biosorption of cadmium, nickel, and lead ions from aqueous solution

Nanocellulose fibers were prepared using physico-chemical treatment of rice straw, characterized and explored for the remediation of some toxic metals from wastewater. Nanocellulose fibers were found to have long rod-like elongated nano fibrillated morphology with average grain size 6 nm. The prepared nanocellulose fibers (0.5 g) in batch experiments showed removal efficiency of 9.7 mg/g Cd (II), 9.42 mg/g Pb(II), and 8.55 mg/g Ni (II) ions from 25 mg/l of metal solution. The sorption process fitted well to both Freundlich and Langmuir isotherms [(R²) Cd (II): 0.92, 0.95; Pb(II): 0.94, 0.97 and Ni (II): 0.97, 0.98]. The regeneration studies signify that nanocellulose fibers can be successively used up to three cycles of regeneration. Nanotech reinforcement to native cellulose significantly enhanced metal removal efficiency compared to rice straw and cellulose fibers, provides new avenues as cost effective, environment-friendly green remediation or can be used as a pre-treatment step prior to chemical decontamination methods for toxic metals.