Chelate extraction of transition metal ions by ethylene diamine diacetic acid with N-substituted octadecyl groups

Niyazi B., Sana S., Nukhet T., Gazi M.

SEPARATION SCIENCE AND TECHNOLOGY, vol.37, no.10, pp.2353-2368, 2002 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 37 Issue: 10
  • Publication Date: 2002
  • Doi Number: 10.1081/ss-120003517
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2353-2368
  • Istanbul Technical University Affiliated: No


An organic-soluble chelating agent, N,N'-di-n-octadecyl ethylenediamine-N,N'-diacetic acid (DOED) has been synthesized in two steps by (i) condensation of dibromoethane with 1-amino octadecane (octadecylamine) and (ii) subsequent reaction with sodium chloro acetate in alcohol-water mixture. The chelating agent in 2-ethylhexanol-cyclohexanol (1:1) solutions shows extremely high chelating ability for Ni(II), Co(II), Cu(II), Fe(111), Cr(III), and Cd(II) ions in neutral aqueous solutions. Extractions take place by the formation of (1:1) ligand-to-metal complexes, and extraction coefficients are in the range 0.74-0.99. The ligand can be regenerated almost quantitatively by washing its complexes with 1M HCl and 0.2 M NaOH solutions successively.