Preconcentration of Zn(II) from Sample Water by Phenyl-iminodiacetic Acid Grafted Multiwalled Carbon Nanotubes

: phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes were prepared by grafted phenyl-iminodiacetic acid groups onto multi-walled carbon nanotubes via a diazotation reaction. The stability of chemically phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes in concentrated hydrochloric acid which was then used as a recycling and pre-concentration reagent for further uses of phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes. The application of this phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes for sorption of a series of metal ions was performed by using different controlling factors such as the pH of metal ion solution and the equilibration shaking time by the static technique. Zn(II) was found to exhibit the highest affinity towards extraction by these phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes phases. The pronounced selectivity was also confirmed from the determined distribution coefficient (Kd) of all the metal ions, showing the highest value reported for Zn(II) to occur by phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes. The potential applications of phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes for selective extraction of Zn(II) to occur from aqueous solution were successfully accomplished as well as pre- concentration of low concentration of Zn(II) (60 pg ml-1) from natural tap water with a pre-concentration factor of 100 for Zn(II) off-line analysis by flame atomic absorption analysis.