Spectroscopic and Thermogravimetric Characterization of Pb(II) Dinonyldithiophosphate: Removal of Pb(II) from Aqueous Solution

Dinonyldithiophosphoric acid (DNDTPA) was prepared by adding phosphorus pentasulfide to nonyl alcohol. The lead dinonyl dithiophosphate complex Pb(DNDTP)2was prepared by mixing a solution of lead(II) with a solution of DNDTPA in ethanol at room temperature. The recovered Pb(DNDTP)2was crystallized in ethanol, and fi ne colorless needles were obtained. The complex was characterised by elemental analysis and IR, UV–vis and atomic absorption spectroscopy. The thermal behavior of Pb(DNDTP)2was investigated by thermogravimetric analysis under a nitrogen atmosphere. Removal of Pb(II) from aqueous media by DNDTPA solutions was investigated. The optimum conditions for extraction, such as the organic solvent, pH of the aqueous phase, time of equilibration, concentration, and effect of anions, were investigated. It was found that DNDTPA is an effective substance for removing Pb(II) from aqueous solution.