An Effective Study on Particulate Matter (PM) Removal Using Graphene Filter

Abstract

Environmental problems have become a serious issue, especially in the region of Delhi-National Capital Region (NCR). The smallest size of particles and molecules dealt with in this study is particulate matter (PM) 2.5, which is a leading contributor of pollution in the environment. We used graphene material in the fabrication of layers of filters because it has revolutionized the domain of electronics and it is shiny. As per the current literature, when we apply honeycomb-like structure layers in the filter fabrication, its quality factor increases almost twice compared with the previous layer. In this study, we will be connecting the filter with a pollution-level measuring meter so that we can recognize the level of contribution of that particle, which will help us deal with the problem more effectively. Graphene is an allotropic form of carbon or, more specifically, it is a single and individual layer of graphite similar to that in a pencil. Graphene, which was named by the German chemist Hanns-Peter Boehm, is a combination of the word “graphite” and “ene”. In 1962, Boehm only described the single-layer carbon foils. Graphene's existence became a trending topic after two scientists, Andre Geim and Konstantin Novoselov, of the University of Manchester, were awarded the Nobel Prize in 2010 in the same domain. Graphene is the first two-dimensional (2D) material discovered that contains a honeycomb-like pattern. It is the strongest and the most rigid material, has the highest known conductivity, and is capable of withstanding high temperatures, besides being valuable in the field of electronics. A standard air filter also works in a similar way: it cleans the air by passing it through a filter medium, which removes particles like dust, air, pet fur, and dirt. As per the survey of the air filter design, we concluded that the first air filter mask was discovered by John and Charles Dean for firefighters from a leather material in 1823, followed by John Sten who improved his house by using a charcoal-based filter design (they were for the firefighters). In 1871, John Tyndall started making a personal respirator. Investigation and research of a long duration resulted in the invention of the high-efficiency particulate air (HEPA) filter. Originally this technology was used to assist soldiers and lab assistants where atomic bombs were created. In Germany, in 1963, Manfred and Klaus Hammer invented air purification techniques for home usage that were manufactured by the companies AG, Austin Air, and Blue Air, but they were very costly and heavy. The technology evolved resulting in the filter becoming cheaper. Austin Air developed a 360° air purifier in 1991, which was mass produced at that time. Technology continued to develop and HEPA filter technology was used by corporations by 2000. Ultraviolet (UV) lightning activated carbon, ozone layer, and photocatalytic oxidation due to ionization, and the technology was implemented in big industries. Graphene-based air filters are three-dimensional (3D) sponge types with a range of 100 nm to 1.5 m per 100 m2/g. Challenges are part and parcel of evolution and revolution. The biggest challenge here is dealing with the PM, which is a pollutant that spreads in air and results in many dangerous diseases. PM 2.5, also known as the condensable particulate matter (CPM), can easily enter the human body due to its small size. One of the most effective ways to reduce PM is by preventing it from being released in the air. Basically, there are two types of PM, namely filterable PM (FPM) and CPM. In this study we tried to filter out both types of PM by using an rGO filter. The commercial filters are not appropriate for electrostatic precipitation because they have electrical conductivity. The electrically conductive nature of the rGO filter, which is porous, can absorb all the particles that are charged by some negative potential applied to the rGO filter. Through rGO filters, we can remove FPMs that were produced from the very first membrane followed by the elimination of CPMs using a condenser. The rGO filter makes an excellent electrostatic precipitator, and it is capable of removing CPMs with a diameter of 2.5 μm less than the actual size very effectively. The rGO filter fulfills our needs and remains unaffected by thermal and acid resistances. Therefore, at high temperature, rGO filters can be used and applied to a PM pollution-emitting source releasing harmful gases containing poisonous and fatal substances.