Environmental Pollution and Nanotechnology

Nanotechnology is capable of developing sensing platforms and systems for the detection of pollutants and helping with remediation technologies. Nanostructured materials are known to be excellent sensors, catalysts, and absorbance because of their remarkably large specific surface area and reactivity.1

Properties of Nanoparticles in Environmental Solutions

Nanostructured materials are famous for their unique properties that appear when they fall into the nanoscale. In effect, nanoparticles manifest completely different and novel properties because of considerable change and increase in their high surface-to-volume ratio making them practically and potentially more reactive than their bulky form. A given material in the nanoscale exhibits properties and distinct physicochemical characteristics when its size decreases to less than 100 nanometers. Furthermore, the elemental properties of materials including color, heat-conducting, light reflecting, strength, magnetic properties, and so forth change rather markedly after they fall in the nanoscopic scale. As an example, some particular plastics possess the strength of steel at the nanoscale. Nano-silicon dioxide crystals are utilized in tennis racket manufacturing to improve the performance of the equipment.

Nanoparticles are classified into four main groups zero-dimensional nanostructures, one-dimensional nanostructures, two-dimensional nanostructures, and three-dimensional nanostructures. The zero-dimensional structures have all three dimensions in the nanometric range. In the case of one-dimensional nanostructures, two dimensions are in the nanoscale and the third dimension remains large and shaped like rods with examples as nanotubes and nanorods. Two-dimensional nanomaterials have only one of their dimensions in the nanoscale the other dimensions are larger than the nanoscopic range showing plane-like structures. Examples of two-dimensional nanostructures are thin films, nanocoatings, and nanolayers. The three-dimensional nanostructures have all their three dimensions outside the nanometric range as nanotubes, nanowires different distributions of nanostructured materials.

Applications of Nanotechnology in Water and Air Pollution Treatment

A broad range of agricultural activities and industrial projects are considered the main cause of soil, water, and air contamination as a whole. As it was mentioned earlier, nanostructured materials show excellent sensing and catalytic absorption characteristics because of their large specific surface areas and high reactivity. Numerous applications of nanotechnology have been commercialized so far as nanoscale coatings and nanosensors have now replaced wasteful and thick polymer coatings that are used to prevent corrosion. There are now nanosensors with applications in detecting aquatic toxins, nanostructured biopolymers for decontamination of heavy metal recycling, nanoscale metals capable of breaking down hazardous materials at room temperature, fine particles to monitor environment purified, and nanostructured materials utilized for catalytic environmental cleanup.1

To find out more, you can read Nano and Micro Materials for a Sustainable Green World: Nano Cellulose Example

Air Pollution Control Using Nanotechnology

Among all the environmental issues, air pollution could be referred to as the world’s most critical environmental issue because of the huge alterations and changes in the natural composition of the atmosphere due to the release of physical, biological, and chemical pollutants to consequently result in life-threatening illnesses and damage to the environment caused by industrial processes such as heavy metals (As, Cr, Pb, Cd, Hg), chlorofluorocarbons (CFCs), organic chemicals, carbon monoxide, carbon dioxide, organic chemicals (VOCs, and dioxins), SO2, biological substances, and sand particles. Human health in particular and the ecosystem (living organisms and vegetation) are directly affected by the polluted air leading to fatal diseases including respiratory, cardiovascular diseases, and cancer. In 2014, it was declared by the World Health Organization that air contamination has caused the death of nearly 7 million people just in 2012. Therefore, the disastrous consequences of environmental pollution require technologies and innovations capable of detecting, receiving, and treating the little concentrations of pollutants in the atmosphere with regard to the properties and capabilities as nanomaterials can offer various solutions and possibilities for air pollution control. Nanostructured materials with their practically fine size and high surface-to-volume ratio have considerable monitoring characteristics. These properties make it possible to design and improve highly accurate and sensitive sensing devices to effectively engage in reactions with pollutants and contaminants and decompose or degrade them into inert and non-toxic products. Furthermore, nanostructured materials can be employed to reduce pollution by replacing toxic materials with other environmentally-friendly materials and materials for coatings technology to improve the resistance against the pollutants in the atmosphere.1

Application of Nanotechnology in Water Treatment

It has been estimated that only 13% of all water reserves on Earth are not trapped in glaciers and ice with only 0.08% of them being clean water. The problem of water contamination is crystal clear to all and is quite challenging to solve the associated problems. However, the progress and advances in nanotechnology can greatly mitigate water quality with several methods using reactive media for disinfection, filtration, bioremediation, and separation. Remediation is a process in which water contaminants are removed, neutralized, or minimized. Remediation technologies are categorized as thermal, biological, and physicochemical methods. There are numerous instances of nanostructured materials and nanoparticles to be employed for the remediation of water including carbon nanotubes, zeolites, nanoparticles of zero-valent iron, single enzyme nanoparticles, self-assembled monolayers on music porous supports, and biopolymers. Iron nanomaterial has been used for water remediation for the past years. The most commonly used system that has been developed to remediate water is called a pump and treat system which involves a way to pump water from the soil up to the surface for treatment and then inject it back into the soil later on using a thermal reactive barrier. Another way to treat and clean water has been developed called permeable reactive barrier (PRB). PRB cleans surface groundwater by pumping it up to the surface and is considered a capable treatment of water and removing contaminants from that. It has been found that some zero-valent metals like iron can be used as capable materials of permeable reactive barriers to minimize hazardous pollutants in water in large quantities. The nanoscale iron is capable of multifunctional applications for water remediation purposes. Generally speaking, zero-valent iron could be categorized into two types nanoscale ZVI and reactive nanoscale Iron product RNIP. These zero-valent iron particles have a diameter of fewer than 200 nanometers.