Efficient removal of high- or low-concentration copper ions using diethylenetriamine-grafted electrospun polyacrylonitrile fibers

The heavy metal copper is a serious hazard to human health and the environment. It is challenging to develop a highly efficient adsorbent that is easy to prepare, low cost, having large adsorption capacity, and non-polluting to the environment. Herein, an aminated electrospun polyacrylonitrile (PAN) staple fiber was prepared by grafting diethylenetriamine (DETA) after a hydrothermal reaction. DETA possessed numerous amino functional groups, thus providing more adsorption sites and higher adsorption capacity for copper ions (Cu2+). The Cu2+ adsorption behavior of the aminated fiber conformed to the pseudo-second-order kinetic model. It not only possessed high adsorption activity in the pH range of 3.0-6.0 and could reach a high saturated adsorption capacity of 349.65 mg g(-1) at high Cu2+ concentrations but also had the ability to reduce the concentration below 1 mg L-1 at low Cu2+ concentrations with a small amount of adsorbent (0.5 mg). After 5 adsorption-desorption experiments, the removal efficiency of Cu2+ was maintained at more than 90%. This aminated PAN fiber is expected to become a candidate material for dealing with Cu2+ pollution.

Automated summary

The heavy metal copper is a hazard to human health and the environment. A highly efficient and low-cost adsorbent, the aminated electrospun polyacrylonitrile (PAN) staple fiber, was prepared by grafting diethylenetriamine (DETA) onto the PAN fiber. The fiber showed high adsorption activity for copper ions and could reduce the concentration below 1 mg/L with a small amount of adsorbent at low copper ion concentrations.