Chapter 13 - Remediation of organic pollutants by potential functionalized nanomaterials

Abstract

In recent years the science of nanomaterials (NMs) has trended toward the fabrication of engineered nanostructures in laboratories and industries for environmental remediation of contaminants (e.g., persistent inorganic-organic pollutants). Methodologies for developing functionalized NMs include organic ligands, enzyme immobilization, inorganic moieties, and surface polymerization. NM functionalization holds the promise of designing new materials and devices for full-scale application of nanotechnology in the environmental field. NMs have shown encouraging outcomes of potential adsorption of pollutants and transforming them into lesser or nontoxic forms. Functionalized metal oxides (MOs) such as Fe0–, TiO2–, and ZnO-doped nanoparticles (NPs), etc., and metal hexacyanoferrates are outpacing bare NMs, which have drawbacks including a negative impact on human health and the ecosystem, lack of reusability and limited activity/selectivity, and cost of treatment. For instance, covering the NP core surface with a capping agent was suggested to protect NMs from corrosion and lower their toxicity. Furthermore, composites of NMs with various ferrites and natural magnetites that can be easily retrieved using an external magnetic field have been designed in order to obtain recoverable and reusable NMs. Properties of some NMs, such as zeolites, can be further tailored by localization of some organic functional groups in order to enhance the selectivity toward specific pollutants. Likewise, functionalized carbon nanotube (CNT)-based sensors have shown higher selectivity and sensitivity to the target analytes. This chapter summarize current information on functionalization techniques of different types of functionalized NMs and their application in the removal of organic pollutants (OPs) such as PAHs, pesticides, organic dyes, and some heavy metals. The chapter concludes with the future scope of functionalized NMs in the area of wastewater treatment industries.