Recent Applications of Carbon Nanotubes for Separation and Enrichment of Lead Ions

Lead is one of the most toxic heavy metals released into the environment through industrial sources. Its direct determination is often a problem due to the presence of relatively complex matrices as well as low content. Thus, the additional separation and preconcentration steps are necessary in the analytical procedures. Carbon nanotubes (CNTs) continue to attract significant interest for these purposes as they exhibit a high specific surface area, exceptional porosities, and numerous adsorption sites. The modified CNTs with active groups, reagents, or materials have been widely explored using more mutual interactions that can significantly improve their sorption capacity and selectivity. This paper summarizes the recent developments from 2017 in the application of carbon nanotubes for the separation of Pb(II) and its enrichment/removal from the matrix components. Attention is given to oxidized CNTs, their modification with complexing compounds, functionalization with metal oxides and polymers, new nanocomposites, and carbon nanotube membranes.