A review on the role of nanomaterials in the removal of organic pollutants from wastewater

Water scarcity will be the prime threat to the millions of the human race across the globe in the future. In the recent report of WHO, about 50% of people will sustain their livings in the water-stressed zones by 2025. As every industrial sector are demanding clean water resource, it is the high time for the development of reliable strategies to recycle the wastewater efficiently. With the conventional techniques, the supply of resources with an exponential increase in the demand is highly challenging. Hence, the alternative, sustainable, and technologically advanced wastewater treatment processes need to be employed instantaneously to compete for the pace. One such promising approach is the use of nano-sized materials with the high surface area and increased surface reactivity in the removal of pollutants from the wastewater. These nanomaterials possess unique properties than their bulk forms enabled the researchers from the various fields to exploit their use in the wastewater treatment processes. As a result, multidisciplinary researches targeting water pollution has increased manifold in recent decades. For instance, the nanomaterials assisted photo-catalysis, membrane filtration, and adsorption processes showed effective results in the removal of organic dyes, heavy metal ions, oil spills, and hydrocarbons, etc. The intrinsic physicochemical, electrical, magnetic properties, and the ease of tailor-made functionalization of nanomaterials identified them as one of the most potent candidates in the water technology. However, the specified challenges such as material toxicity, stability, recovery, fouling, etc. are existing in the use of nanomaterials and several successful innovations are prospering to counteract them in recent years. With such high intentness of these nano-sized materials, the present chapter provides a comprehensive report on the pivotal researches made on the wastewater treatment processes.