Heavy Metals Removal Using Nanostructured Carbon-Based Composites in the Presence of Various Organic Compounds

Due to intense development of civilization and human activity, there is a continuous increase of the heavy metals concentration in the environment. This phenomenon is particularly visible in inland surface waters, marine coastal waters, soil waters as well as shallow groundwater. Heavy metals are impurities that pose a particular threat to organisms. In plants, they may reduce nutrient uptake, which contributes to growth inhibition, chlorosis, and necrosis. In animals, heavy metals may damage kidneys and liver, disrupt nervous and cardiovascular systems, and lead to infertility and tumor growth. Taking these facts into account, it can be stated that effective removal of heavy metal ions from aqueous solutions is highly important. Innovative composites based on carbon can be the solution to the above problem. Due to their unique properties—large specific surface area, appropriate porosity, and high concentration of surface active centers—they assure excellent adsorption properties in relation to low- and high-molecular weight adsorbates such as metal ions, dyes, drugs, pesticides, and polymers. Sorbents composed of the core made of one or two heavy metals, and the shell consisting of carbon and silica is the special group of these materials. Some of them have magnetic properties, thanks to which the used solid covered with adsorbed impurities can be easily separated from the solution. Few studies on composite sorption capacity for heavy metal ions in the presence of other environmental pollutants (e.g., synthetic polymers, surfactants) were currently conducted. Nevertheless, this issue has not been sufficiently explored so far and requires further research.