Thermodynamic parameters for the binding of sulfate by open chain polyammonium cations.
The interaction of sulfate with some open chain polyammonium cations was quantitatively studied by potentiometric (H(+)-glass electrode) measurements. Enthalpy changes, for some systems, were determined calorimetrically. Some literature data were also considered in the discussion of results. In all the systems, A(SO4)Hi(i-2) species are formed (i = 1, ...m; m = maximum protonation degree of amine), and, for i > or = 4, also A(SO4)2Hi(i-4) species were found. Both the stability and the formation enthalpies, for these complexes, are a direct function of the charges of reactants, and some empirical relationships are reported. A small, but significant, difference was found between the stability of unsubstituted and N-alkylsubstituted polyammonium cation-sulfate complexes.
Foti
Claudia
C
Dipartimento di Chimica Inorganica, Chimica Analitica e Chimica Fisica, Università di Messina, Salita Sperone, 31, I-98166 Messina, Vill. S. Agata, Italy. foti@chem.unime.it
Pettignano
Alberto
A
Sammartano
Silvio
S
D002151:Calorimetry; D002412:Cations / Q000737:chemistry; D006801:Humans; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*; D013816:Thermodynamics
D002412:Cations; D000644:Quaternary Ammonium Compounds; D013431:Sulfates