Preparation and Application of Graphene-Based Materials for Heavy Metal Removal in Tobacco Industry: A Review

Heavy metals are nondegradable in the natural environment and harmful to the ecological system and human beings, causing an increased environmental pollution problem. It is required to remove heavy metals from wastewater urgently. Up until now, various methods have been involved in the heavy metal removals, such as chemical precipitation, chemical reduction, electrochemical, membrane separation, ion exchange, biological, and adsorption methods. Among them, adsorption by graphene-based materials has attracted much more attentions for the removal of heavy metals from wastewater systems in recent years, arising due to their large specific surface area, high adsorption capacity, high removal efficiency, and good recyclability. Therefore, it is quite important to review the heavy metal removal with the graphene-based material. In this review, we have summarized the physicochemical property and preparation methods of graphene and their adsorption property to heavy metals. The influencing parameters for the removal of heavy metals by graphene-based materials have been discussed. In addition, the modification of graphene-based materials to enhance their adsorption capability for heavy metal removal is also reviewed. The heavy metal removal by modified graphene-based materials in the tobacco industry has been especially described in detail. Finally, the future trend for graphene-based materials in the field of heavy metal wastewater treatment is proposed. This knowledge will have great impacts on the field and facilitate the researchers to seek the new functionalization method for graphene-based materials with high adsorption capacity to heavy metals in the tobacco industry in the future.