Treatment of Hazardous Engineered Nanomaterials by Supermagnetized α-Cellulose Fibers of Renewable Paper-Waste Origin

Engineered nanomaterials (ENMs) are posing detrimental ramifications to human health in general and aquatic wildlife in particular. Herein, we report treatment of three types of ENMs, namely, CuO, CoO, and ZnO by a magnetic composite (Fe₃O₄NPs) with α-cellulose fibers of paper-waste origin (PW-αCF). The removal efficiency of Fe₃O₄@PW-αCFs for (CuO), (CoO), and (ZnO) was obtained to be 850, 946, and 929 mg·g^-1, respectively. The adsorption efficacy observed optimum at pH 6 to 7; thus, this system was based on hydroxyl groups of PW-αCFs. Also, to validate the real-world applications, the ENM removal capacity of Fe₃O₄@PW-αCFs was assessed in different water sources such as a river, pond, and wastewater (spiked together with CuO, CoO, and ZnO). Furthermore, unprecedented energy dispersive spectrometric (EDS) mapping was employed to illustrate the ENMs loading on Fe₃O₄@PW-αCFs and to reveal the role of Fe₃O₄ NPs surface in the deposition of heavyweight aggregates of ENMs. The robust integration of ENMs onto Fe₃O₄@PW-αCF surfaces rules-out the ENMs leaching back into the aqueous media. Hence, abundant availability and their functionalities such as hydroxyl groups, lightweight, high-surface area, and rapid magnetic separation, proved Fe₃O₄@PW-αCFs as an attractive bionanocomposite material for ENMs remediation and utilization in various applications.