Open AccessExchange of Some Divalent Metal Cations and Their Effect on the Dissociation of Iron(III) Phosphate
Author(s) -
S. Mustafa,
Abdul Naeem,
N. Rehana,
T. Hussain
Publication year - 1996
Publication title -
adsorption science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.682
H-Index - 36
eISSN - 2048-4038
pISSN - 0263-6174
DOI - 10.1177/026361749601300403
Subject(s) - chemistry , potentiometric titration , inorganic chemistry , monobasic acid , phosphate , dissociation (chemistry) , divalent , alkali metal , dissociation constant , titration , ion exchange , iron phosphate , metal , ion , organic chemistry , biochemistry , receptor
Potentiometric titrations of iron(III) phosphate have shown an apparently weak monobasic acid behaviour towards alkali, alkaline earth and divalent transition metal ions. The selectivity sequence and dissociation of the exchanger was found to increase in the order Cu 2+ > Zn 2+ > Ni 2+ > Ca 2+ > K + . The dissociation constants of iron(III) phosphate have been determined from Potentiometric titration data in the temperature range 303–323 K. In addition, the exchange of Cu 2+ , Zn 2+ and Co 2+ on iron(III) phosphate and the effect of these ions on dissociation were also studied as a function of concentration, temperature and solution pH value. The thermodynamic parameters ΔH 0 , ΔS 0 and ΔG 0 for the dissociation of iron(III) phosphate are also presented.