Complex Formation Between Ferric Ion and Phosphoric Acid

[摘要] Complex formation between ferric ion and phosphoric acid has been studied in the wide range of the acid concentration(0¡­40%) by uv-visible spectroscopy and by characterization of the isolated products. The electronic spectra of Fe(¥²)-containing phosphoric acid solutions exhibit two visible bands at 19.2 and 24.1 kK, which are characteristic of Fe(¥²)-phosphate complex formation. The measurements of acid concentration dependence of the opical density of the 24.1 kK band indicates the presence of two distinct forms of Fe(¥²)-phosphate complexes possibly [Fe(HxPO4]x+ and [Fe2(HxPO4)](3+x)+. The 1:1 complex has been isolated for characterization, and the phosphate ion was found to be coordinated to the metal in monobasic state whereas the isolation of the dimeric species was unsuccessful.

[学科分类] 化学（综合）