How Environmental Chemicals of Concern Emerge: ILs and HNTs

Chemicals of concern may emerge in our environment in many ways. Two distinct ways are through the design of the compound or by molecules/functionalities added to the original compound. In this chapter, we will use ionic liquidsIonic liquids (ILs) and halloysite nanotubes (HNTsHalloysite nanotubes (HNTs)) to illustrate these two ways. ILs are salts that are typically composed of organic cations and inorganic anions. While they were initially promoted as “green” solvents, this characterization is not necessarily true. The potential number and uses for ILs seem almost limitless. HNTsHalloysite nanotubes (HNTs) are a form of naturally occurring clay, possessing mostly a nanotubular structure and a similar chemical composition to kaolin. The tubular morphology and the aluminum silicate structure of HNTsHalloysite nanotubes (HNTs) have allowed them extensive use in science, engineering, and medicine. The growth of the biorefineryBiorefinery and green chemistryGreen chemistry, circular chemistry, and sustainability will provide increasing access of these compounds into the environment. This extended use of both ILs and HNTsHalloysite nanotubes (HNTs) increases their presence in the environment. While the ILs which may be toxic depending upon their composition, HNTsHalloysite nanotubes (HNTs) may become toxic due to what is loaded in/on them. While the utility of these chemicals is unquestionable, understanding their environmental behavior, fate, and effects is critical.