Nanopolymer cellulose synthesis from paper board sludge and its utilization for heavy metal adsorption

Abstract

Water is a crucial resource and when industrial and urban wastes are discharged newlineinto it beyond its natural cleansing ability, it poses a significant risk, especially in terms of newlineheavy metal pollution. Global challenges arise from chromium (Cr) contamination due to its newlinewidespread use in various industrial processes, specifically in the tanning industry. This sector newlineis one of the most polluting industries due to substantial amounts of chromium being newlinedischarged into environment. Despite the involvement of various chemical methods in newlinechromium removal, their high costs and the generation of toxic sludge, need economically newlineviable and eco-friendly alternative technologies. Nevertheless, there is a growing focus on the newlinecreation of cost-effective and recyclable adsorbents for the removal of pollutants from polluted newlinewater. Nanocellulose derived from agricultural residue and industrial wastes possessed robust newlinemechanical strength, high functionality, biodegradability and a specific surface area. newlineRecognizing this, the current study was undertaken to explore the potential of nanocellulose newlinederived from paperboard mill sludge in removing chromium from tannery effluents through newlinethe biosorption process. The need for wastewater reuse arises due to the insufficient availability newlineof water for irrigation and domestic purposes. Given this circumstance, the tannery effluent, newlinetreated using the adsorption process, was employed in conjunction with nanocellulose obtained newlinethrough citric acid and formic acid digestion processes. newlineIn this study, paperboard mill sludge which consisted of 23.18, 36.57 and newline16.25 per cent of lignin, cellulose and hemicellulose content, respectively, that paved way newlinefor derivation of nanocellulose. Among the two methods, the citric acid hydrolysis process newlineresulted in a higher cellulose content compared to the alternative method involving formic newlineacid digestion of the paperboard mill sludge. Therefore, cellulose obtained through both newlinedigestion methods was utilized in the synthesis of nanocellulose.