Recent Advancements in the Field of Chitosan/Cellulose-Based Nanocomposites for Maximizing Arsenic Removal from Aqueous Environment.

Water remediation, acknowledged as a significant scientific topic, guarantees the safety of drinking water, considering the diverse range of pollutants that can contaminate it. Among these pollutants, arsenic stands out as a particularly severe threat to human health, significantly compromising the overall quality of life. Despite widespread awareness of the harmful effects of arsenic poisoning, there remains a scarcity of literature on the utilization of biobased polymers as sustainable alternatives for comprehensive arsenic removal in practical concern. Cellulose and chitosan, two of the most prevalent biopolymers in nature, provide a wide range of potential benefits in cutting-edge industries, including water remediation. Nanocomposites derived from cellulose and chitosan offer numerous advantages over their larger equivalents, including high chelating properties, cost-effective production, strength, integrity during usage, and the potential to close the recycling loop. Within the sphere of arsenic remediation, this Review outlines the selection criteria for novel cellulose/chitosan-nanocomposites, such as scalability in synthesis, complete arsenic removal, and recyclability for technical significance. Especially, it aims to give an overview of the historical development of research in cellulose and chitosan, techniques for enhancing their performance, the current state of the art of the field, and the mechanisms underlying the adsorption of arsenic using cellulose/chitosan nanocomposites. Additionally, it extensively discusses the impact of shape and size on adsorbent efficiency, highlighting the crucial role of physical characteristics in optimizing performance for practical applications. Furthermore, this Review addresses regeneration, reuse, and future prospects for chitosan/cellulose-nanocomposites, which bear practical relevance. Therefore, this Review underscores the significant research gap and offers insights into refining the structural features of adsorbents to improve total inorganic arsenic removal, thereby facilitating the transition of green-material-based technology into operational use.

Spherically shaped pectin-g-poly(amidoxime)-Fe complex: A promising innovative pathway to tailor a new material in high amidoxime functionalization for fluoride adsorption.

Pectin was hydrolyzed and was processed in spherically-shaped structure through calcium crosslinker. The synthesized spherical-bead structure was surface functionalized by acrylonitrile grafting reaction, which extends the applications of pectin followed by derivatization with hydroxylamine. The matrix was further decorated with the iron metal to enhance the practical applicability in the aqueous system. The chemical structures were characterized via gravimetric analysis, FTIR, SEM-EDX, elemental analysis, XPS and XRD. The results supported the exceptional uniformity with the presence of substantial receptor amidoxime groups in morphology and elemental composition. The process of adsorption was concluded with good adsorption capacity with iron-impregnated-amidoxime. The presence of S2O32-, SO42-, and NO3- had an insignificant influence on fluoride uptake excluding Cl- and PO43- in a binary/mixture solutions. The adsorption data were excellently expressed by the Freundlich isotherm model (R2 > 0.998) which suggests that the surface of the ligand is multifunctional. The kinetic data was determined and pseudo-second-order rate equation showed well-fit (R2 > 0.998) to the presented data. The findings indicate that Fe-impregnated poly(amidoxime) is a cost-effective and eco-friendly promising adsorbent for fluoride removal even at trace level and a wide optimum pH range due to better aqueous dispersibility of pendent groups responsible for the sorption application.