RESUMO
Good quality of water determines the healthy life of living beings on this earth. The cleanliness of water was interrupted by the pollutants emerging out of several human activities. Industrialization, urbanization, heavy population, and improper disposal of wastes are found to be the major reasons for the contamination of water. Globally, the inclusion of volatile organic compounds (VOCs) and heavy metals released by manufacturing industries, pharmaceuticals, and petrochemical processes have created environmental issues. The toxic nature of these pollutants has led researchers, scientists, and industries to exhibit concern toward the complete eradication of them. In this scenario, the development of wastewater treatment methodologies at low cost and in an eco-friendly way had gained importance at the international level. Recently, bio-based technologies were considered for environmental remedies. Biofiltration-based works have shown a significant result for the removal of volatile organic compounds and heavy metals in the treatment of wastewater. This was done with several biological sources such as bacteria, fungi, algae, plants, yeasts, etc. The biofiltration technique is cost-effective, simple, biocompatible, sustainable, and eco-friendly compared to conventional techniques. This review article provides deep insight into biofiltration technologies engaged in the removal of volatile organic compounds and heavy metals in the wastewater treatment process.
Assuntos
Poluentes Ambientais , Metais Pesados , Compostos Orgânicos Voláteis , Poluentes Químicos da Água , Biodegradação Ambiental , Humanos , Águas Residuárias , ÁguaRESUMO
The treatment of industrial waste and harmful bacteria is an important topic due to the release of toxins from the industrial pollutants that damage the water resources. These harmful sources frighten the life of every organism which was later developed as the carcinogenic and mutagenic agents. Therefore, the current study focuses on the breakdown or degradation of 4-chlorophenol and the antibacterial activity against Escherichia coli (E. coli). As a well-known catalyst, pure titanium-di-oxide (TiO2) had not shown the photocatalytic activity in the visible light region. Hence, band position of TiO2 need to be shifted to bring out the absorption in the visible light region. For this purpose, the n-type TiO2 nanocrystalline material's band gap got varied by adding different ratios of p-type CuO. The result had appeared in the formation of p (CuO) - n (TiO2) junction synthesized from sol-gel followed by chemical precipitation methods. The optical band gap value was determined by Kubelka-Munk (K-M) plot through UV-Vis diffusive reflectance spectroscopy (DRS). Further, the comprehensive mechanism and the results of photocatalytic and antibacterial activities were discussed in detail. These investigations are made for tuning the TiO2 catalyst towards improving or eliminating the existing various environmental damages.