Synthesis of Graphene Derivatives and The Designing of Hybrid Filter For Water Purification

Abstract

Recognizing the significance of graphene and its derivatives, the overarching goal is to develop advanced composites based on graphene derivatives that have improved properties for treating wastewater containing a variety of organic, inorganic, and /or pathogenic pollutants using various techniques. We have successfully synthesized graphene derivatives, including GO and rGO, from various organic sources like graphite, coal, and rice husk (G-GO, G-rGO, C-GO, C- rGO, RH-GO, RH-rGO). Our primary objective was to assess the effectiveness and quality of these synthesized materials for wastewater treatment. Subsequently, we employed the most efficient graphene derivatives (G-GO, G-rGO) in combination with a polyurethane (PU) polymer substrate to create a cost-effective material called GOPU. We further enhanced the performance of this graphene polyurethane composite by adjusting the size of the polyurethane substrate into micro-sized GOPU granules and by substituting GO or rGO with a highly efficient novel GO-Fe3O4-PEI composite for adsorptive removal of various organic, inorganic, and pathogenic pollutants. Additionally, wastewater treatment was performed using a ternary photocatalyst, TiO2@Gd2O3@g-C3N4, to promote photocatalytic destruction of a broad spectrum of organic, inorganic, and pathogenic pollutants. Further, to enhance the catalyst's efficiency and make it functional even without light, we introduced carbon nanotubes (CNT). We developed an innovative day-night photocatalyst through a hydrothermal method called g- C3N4@Gd2O3@CNT, which exhibited a post-illumination catalytic effect. Furthermore, we designed a unique photoreactor called a Flatplate photoreactor, featuring a flat glass reactor panel loaded with a polymeric day-night photocatalyst, g-C3N4@Gd2O3@CNT@PU. This photoreactor was employed for efficient wastewater treatment. This current study explores an innovative approach and route for wastewater treatment by leveraging newly developed composites based on graphene derivatives. It offers valuable insights into the effectiveness of multifunctional graphene derivative-based day-night catalysts in wastewater treatment and their versatile application in other fields.