Open AccessAdsorption of H+, OH− and Background Electrolyte Ions on Alumina — Point of Zero Charge, Triple Layer Model (TLM) Parameters and Thermodynamic Parameters
Author(s) -
Taiwei Chu,
Jinzhou Du,
Tao Zuyi
Publication year - 1997
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 - 10.1177/026361749701500606
Subject(s) - chemistry , point of zero charge , aqueous solution , adsorption , electrolyte , surface charge , titration , dissociation (chemistry) , analytical chemistry (journal) , dissociation constant , ion , equilibrium constant , gibbs free energy , effective nuclear charge , inorganic chemistry , atmospheric temperature range , thermodynamics , chromatography , organic chemistry , physics , receptor , electrode , biochemistry
The surface charge σ 0 on aqueous suspensions of alumina was measured as a function of pH in various NaNO 3 concentrations and at different temperatures. The values of the point of zero charge (p.z.c.), pK 1(int) , pK 2(int) , pK Na+(int) and pK NO3–(int) for alumina suspended in NaNO 3 solutions were obtained in the temperature range 17–45°C from potentiometrie titration data. The values of ΔS 0 and ΔH 0 of the dissociation equilibria and complexation equilibria were calculated from these equilibrium constants. Standard Gibbs energies, enthalpies and entropies for proton adsorption on alumina were also obtained. The surface charge σ 0 on aqueous suspensions of alumina was measured as a function of pH and concentration of Ca(NO 3 ) 2 or Na 2 SO 4 solution.