Extraction and preconcentration of vanadium from aqueous solutions using multi-walled carbon nanotubes decorated with magnetic nanoparticles

In this work MWCNTs-Fe3O4 nanocomposite was used as an adsorbent for extraction and preconcentration of vanadium prior to inductively coupled plasma optical emission spectrometry determination. The magnetic MWCNTs with adsorbed analytes can be easily separated from the aqueous solution by using an external magnet without additional centrifugation or filtration of the sample. Due to the high surface area of MWCNTs, satisfactory concentration factor and extraction recovery can be achieved with only 5 mg nanocomposite in 5 min. The effects of pH, sorbent amount, eluent type, chelating reagent concentration, sample volume and time on the recovery of the V(V) were investigated. Under the optimum conditions, the detection limit for V(V) was 0.12 µg L^−1.