Composite Based on Chitosan and Graphene Oxide

Abstract

Graphene oxide (GO) and composites based on it are promising candidates for the implementation of the process of purification from polluting ions of heavy metals and organic compounds in waste and industrial waters. However, the limitations of the use of GO for water treatment are associated with the difficulties of its regeneration and extraction from aqueous solutions due to high hydrophobicity and dispersibility. We have synthesized graphene oxide by the modified Hammer method, which allows further functionalization. To improve the method of wastewater treatment, we obtained a new GO/chitosan nanocomposite by covalent and non-covalent grafting of chitosan to GO, so in the case of a covalent bond, we used thionyl chloride with further sonification of the mixture. Characterization and study of the morphology of the obtained graphene oxide by IR spectroscopy, X-ray diffraction and TEM analysis, which confirmed the possibility of the crosslinking reaction of GO and chitosan through the carbonyl and epoxy groups of GO located on the surface of the graphene oxide layer, which were obtained in large quantities due to the fact that we modified the method obtaining graphene oxide. The synthesized composites were tested as filters for cleaning the waters of the Caspian Sea, which is prone to oil pollution due to its proximity to the oil sector, and the amount of heavy metals is also increased in these waters.