Chitin and Chitosan in Wastewater Treatment

As hazardous organic and inorganic pollutants are released into the aquatic environment at an increasing rate, water quality is continually declining. The elimination of such contaminants 352from the water system is a developing field of study. Recently, biodegradable and biocompatible natural additives have gained attraction, due to their immense potential to lessen contaminants in wastewater. Chitosan and its composites have been recognized as valuable absorbents, owing to their cost-effectiveness, widespread availability, presence of hydroxyl and amino groups, and capacity to effectively eliminate various pollutants from wastewater. The practical use of chitosan-based nano-biocomposites is hindered by many challenges, such as limited selectivity, inadequate mechanical strength, and susceptibility to solubility issues in acidic conditions. Consequently, a variety of modification approaches were investigated in order to enhance the physicochemical characteristics of chitosan for the aim of treatment of wastewater. The efficacy of chitosan-based nanocomposites in the removal of microplastics, pesticides, and metals from wastewater has been well-documented. In recent times, there has been a notable surge in interest surrounding the use of chitosan-doped nanoparticles as nanocomposites for the purpose of water purification. Hence, the utilization of chitosan with appropriate modifications in the creation of such absorbents represents a pioneering approach to address the elimination of detrimental contaminants within aquatic environments, ultimately aiming to ensure the availability of safe drinking water on a global scale. The advancements in the synthesis of sorbents containing sugars, in particular chitosan biopolymers, and their uses in wastewater treatment are covered in this chapter.