Development of Indoor Air Filter for VOCs

Abstract

Abstract Formaldehyde is the key pollutant deteriorating indoor air quality. Due to the excessive interior decoration and the lack of appropriate regulation and control strategy, sometimes the cancer risk caused by formaldehyde is 100 to 1,000 times greater than the acceptable level in many office buildings and houses. As United Nations Sustainable Development Goal 3.9.1 states that mortality rate is attributed to household and ambient air pollution, constant surge in mortality rate is related to poor air quality. To remove these pollutants activated carbon plays an essential role, as its structure is highly porous with high surface area, which helps in adsorbing pollutants on its surface. This project focuses on the development of an air purifier using activated carbon produced from the pyrolysis of rice straw-based biochar to remove formaldehyde from enclosed spaces. The produced activated carbon was then subjected to chemical analysis, which included SEM, EDS and BET to determine the morphology, elemental composition and its surface area. Activated carbon was placed in the form of beads inside the three-layered air purifier made using locally sourced material. The three-layered amalgam consists of a pre-filter, HEPA filter and our own activated carbon filter. To determine the removal efficiency of our air purifier, Clen-Air, experiments were carried out in a closed office space. The results deduced were based on the relevant studies obtained from literature, which stated that formaldehyde levels reduce to 50% of the maximum in first 15 minutes and by next 25 minutes, it reduces to 0%. Many products are available in the market globally which filters the VOCs but our belief in sustainable development has compelled us to use locally available material particularly in this case thereby ultimately reducing the cost significantly.