Cellulose-Based Nanomaterials (Nanobioadsorbents) for Recovery of Valuable Metals from Wastewater: A Review

In recent times, water pollution has become an issue of major concern. Various materials and techniques have been adopted for the purification of water. Among many, cellulose-based nanomaterials have gained valuable use in water remediation processes. These cellulose-based materials are highly biocompatible, abundantly available natural biopolymers and enjoy the advantage of containing many functional groups. The functional groups attached to cellulose biopolymers ensure their capability of modification with various nanoparticles like silver (Ag), graphene oxide (GO), and zinc oxide (ZnO) nanoparticles. These can then be easily applied for the remediation of wastewater by removing pollutants like organic dyes, microbial species, various drugs and heavy metal ions as well. In this chapter designing of various cellulose-based nano-materials has been discussed for the extraction of valuable metals from various wastewater. Mainly static and dynamic absorption processes through cellulose-based nano-materials have been also explained. Adsorption by various chemical transformations such as reduction, chelation and electrostatic interaction are discussed for the extraction of various metals from different wastewater sources. Lastly, composite systems consisting of cellulose and metal oxide nanoparticles have been reviewed for the extraction of rare earth metals from the mining industry. Metals from the recycling of battery and semiconductor devices that mostly constitute noble metals and rare earth elements are also discussed in this chapter.