Fullerol-facilitated transport of copper ions in water-saturated porous media: Influencing factors and mechanism.

The environmental safety of carbon nanomaterials (CNMs) has become a hot spot of worldwide research work. The high stability, mobility and adsorption capability of CNMs may give rise to the enhancement of heavy metal transport. However, the understanding of facilitated transport of heavy metal ions by CNMs is still limited. In this research, fullerol nanoparticles (C60 (OH)n ) were used as a typical CNM to investigate its effect on Cu2+ transport in the water-saturated porous media. Column experiments showed that C60 (OH)n could facilitate the transport of Cu2+ . Meanwhile, flow velocity showed little impact on the facilitated transport while pH and fullerol concentration played an important role. The mechanism of fullerol-facilitated transport of Cu2+ was mainly due to the much higher adsorption capacity of C60 (OH)n than that of the porous media. Besides, the existence of C60 (OH)n decreased the adsorption kinetics of Cu2+ on the porous media, which led to a decreasing chance for Cu2+ to be retained and thus enhanced the transport of Cu2+ .