STUDY OF THE EXTRACTION OF CHROMIUM(Ⅵ) WITH A NEW EXTRACTION REAGENT N,N′-DI(DODECYL)-ETHYLENEDIAMINE

A new extraction reagent,N′N-di(dodecyl)-ethylenediamine (expressed as R2en below) was synthesized,and its composition and structure were analyzed and proved by elementary analysis,IR spectrometry,ESI and 1HNMR.Chloroform solution of R2en was used in the study of its extraction behavior toward chromium(Ⅵ) ion.Various factors (including acidity of the aqueous solution containing Cr(Ⅵ),concentration of Cr(Ⅵ) in solution,concentration of R2en in CHCl3,ratio of volume of water phase and CHCl3 phase and temperature of the extraction system) affecting the rate of extraction were tested.Mole ratio of R2en to Cr(Ⅵ) was found to be 2 to 1.Chromium(Ⅵ) in the organic phase was stripped effectively by 1 mol·L-1 NaOH solution,and the CHCl3 was recovered and re-used in succeeding extraction.The rate of back-extraction was 98.11%.