Nano Silica Based Adsorbants for Removal of Heavy Metals and Microbial Contaminants from Water

In aquatic biosystems, where symbiotic activities could be affected, such as by reducing photosynthetic activity, toxic dyes, metal ions, and organic contaminants present a serious environmental risk (Ghorai et al., 2014). Water is still essential to modern society, the environment, and human development, but the byproducts of water use are industrial and municipal wastewaters. Consequently, treating wastewaters to make them reusable is not only a crucial task but also a pressing issue that needs to be resolved. Metals like zinc, copper, lead, cadmium, nickel, and chromium found in industrial wastewater from numerous factories can harm the environment. Chemical precipitation, which employs an alkaline solution to increase pH and facilitate the development of heavy metal hydroxide precipitate, is the method most frequently employed for treating wastewaters containing heavy metals. Filtration or other solid/liquid separation procedures are then performed. Even though the chemical precipitation procedure is a highly effective way to remove heavy metals, the heavy metal sludge it produces is classified as hazardous solid waste and must be treated properly (Lee et al., 2007).