Environmental contamination is the most serious global threat to our ecosystem. Over the last few decades, there has been a rise in environmental sensitivity. Indiscriminate use of water resources beyond their regeneration limits has resulted in the current water crisis that the world is experiencing. Hazardous effluents from textile industries and resistant microbes are significant sources for water deterioration with detrimental impacts on both biotic and abiotic components. Effective solutions to water purification are the need of the hour. Hydrogels possess unique properties with potential as effective adsorbents for dyes and hazardous metal ions enrichment from wastewater. Nanocomposites are a new class of advanced materials for technology. Nanocomposite hydrogels with reinforcing nanofillers exhibit noticeably superior properties as compared to conventional hydrogels and have the potential to become efficient adsorbents for such pollutants. Present chapter provides a thorough overview of the role of nanocomposites in water pollution alleviation techniques.
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The biggest global threat to our environment is pollution. The need for environmental protection has increased during the last few decades. Technological advances in the twenty-first century and the industrial revolution have led to a sharp rise in water contamination. The globe is currently experiencing a water crisis as a result of the indiscriminate use of water resources beyond their capacity for regeneration and the massive amounts of waste water that are produced every day. Water pollution has an impact on both the biotic and abiotic elements of the environment. The power of chemical companies to harm flora and fauna sends a worrisome message to society. Aquatic biosystems have substantially degraded in recent years due to the rise of pathogenic microorganisms, synthetic dyes, and the buildup of dangerous metal ions (Abu Elella et al., 2021b). The majority of these effluents contain hazardous compounds that are non-biodegradable and harm exposed organisms and marine life. Untreated water contaminants are frequently released into water reservoirs and are one of the most prominent sources are hazardous effluents from the textile sector. Contamination of water is a serious environmental issue that limits access to safe drinking water.
Heavy metals are poisonous to humans and non-biodegradable contaminants. Transition metals, certain metalloids, lanthanides, and actinides all contain elements with an ill-defined group. Metals such as Pb, Cd, Cu, Al, Co, Hg, and others have been considered contaminated when their concentration in a medium exceeds a specific threshold and has a negative influence on the environment. Different metal processing sectors, alloy-based businesses, and mining operations are the main sources of contamination of this metal in the environment. Heavy metals in drinking water have permitted limits, such as 0.0I for As, 0.400 for Mn, 0.015 for U, 0.003 for Cd, and 0.006 for Hg (WHO,1990). Irrigation is one of the primary sources of heavy metal contamination in water bodies. These bodies of water employ various aspects of the environment and, as a result, have an impact on the health of living things via the food chain (Meade,1995)
Toxic metal ions and organic contaminants are the main causes of environmental pollution. Various research groups are looking for powerful tactics and practical ways to eliminate these pollutants. Biological degradation, ion exchange, coagulation-flocculation, chemical precipitation, adsorption, enhanced oxidation processes, photo catalysis, membrane filtration, solvent extraction, and adsorption methods have all been utilized to remove these contaminants from water bodies and make the water fit for consumption (Zhong et al.,1996). Industrial wastewaters can be cleaned up by using re-precipitation techniques to get rid of heavy metal ions like hydroxides, carbonates, sulphides, and sulphates (Feng et al.,2000). Water contamination is typically treated and reduced using membrane filtration and ion exchange resins (Oliva et al.,2011., Korus & Loska.,2009). The above solutions, however, have gotten less attention because of their high operational expenses. Another strategy for separating heavy metals is solvent extraction. A wide range of extractants and chemical ligands can be used with this simple operation method. The process of adsorption is another way to eliminate metals and their ions from water (Al-Asheh et al.,2008). The adsorption method is the most dependable and effective technology because of its simplicity, affordability, and lack of harmful sludge production. Utilizing a range of adsorbents, substantial research has been done on the use of adsorption as a water treatment technology to remove colours and other impurities. Adsorption is viewed as a potential strategy for eliminating dye wastes due to its good removal capabilities at low concentrations (Pai et al., 2021).