Review of scientific technology-based solutions for vehicular pollution control

Numerous management strategies are implemented for the improvement in urban air quality worldwide, including control at tailpipe emissions. Control at the source is one of the best practices for pollution control, but this approach needs very stringent enforcement, public support, and monitoring for implementation. Besides, scientific processes-based technology to remove the pollutants from the ambient environment is also one of the approaches to improve air quality; however, high efficiency of such devices is one of the major challenges for the researchers. The present article is an attempt to review the state-of-the-art literature on such science-based technologies used to remove the pollutants from the ambient environment. The article highlighted the issues of high spatiotemporal variations in air pollution level in urban areas and methodologies available for the removal of pollutants. The efficiency of developed prototypes/devices using these processes is also compared worldwide. The technologies are available for particulate matter, and/or for gaseous pollutants. The air purification devices are designed and developed using scientific principles of bio-filtration, ionization, phytoremediation, photo-catalytic, and physical filtration. Based on the literature, it is found that ionization and physical filtration can remove particulate matter in the range of 61–95% and ~ 70%, respectively, while phytoremediation can remove in the range of 24–40%. The phytoremediation can remove NO_x in the range of 10–15%. The efficiency of devices varies as pollution load and particle size distribution pattern varies. It is suggested that such control devices would be very useful in the reduction in air pollution at the hot spot area having high spatiotemporal variations.