A computer program was developed to elaborate the titration curves of amphoteric surfaces according to the double layer theory. The zpc, identified from the intersection point of the titration curves carried out at different ionic strengths, fell at pH 3.15, 9.45 and 7.65 for Si, AI and Fe hydroxides, respectively. The Stern model described quite satisfactorily the relation between σ0and ψ0. Some problem was presented by Si surfaces which were then treated by a different calculation procedure. The δ values, the Stern layer thickness, were very high for the SI surfaces and increased with decreasing ionic strength. A different behaviour was showed by AI and Fe hydroxides; in these cases δ values were very low and increased with increasing electrolyte concentration. These results were discussed in terms of surface structures and activity of the supporting electrolyte.

Describing the adsorption of potential determining ions on variable charge mineral surfaces / Melis, Pietro; Dixit, S.; Gessa, Carlo Emanuele; Premoli, Alessandra Maria. - In: STUDI SASSARESI. SEZIONE 3: ANNALI DELLA FACOLTÀ DI AGRARIA DELL'UNIVERSITÀ DI SASSARI. - ISSN 0562-2662. - 30:(1983), pp. 137-148.

Describing the adsorption of potential determining ions on variable charge mineral surfaces

Melis, Pietro;Premoli, Alessandra Maria
1983-01-01

Abstract

A computer program was developed to elaborate the titration curves of amphoteric surfaces according to the double layer theory. The zpc, identified from the intersection point of the titration curves carried out at different ionic strengths, fell at pH 3.15, 9.45 and 7.65 for Si, AI and Fe hydroxides, respectively. The Stern model described quite satisfactorily the relation between σ0and ψ0. Some problem was presented by Si surfaces which were then treated by a different calculation procedure. The δ values, the Stern layer thickness, were very high for the SI surfaces and increased with decreasing ionic strength. A different behaviour was showed by AI and Fe hydroxides; in these cases δ values were very low and increased with increasing electrolyte concentration. These results were discussed in terms of surface structures and activity of the supporting electrolyte.
1983
Describing the adsorption of potential determining ions on variable charge mineral surfaces / Melis, Pietro; Dixit, S.; Gessa, Carlo Emanuele; Premoli, Alessandra Maria. - In: STUDI SASSARESI. SEZIONE 3: ANNALI DELLA FACOLTÀ DI AGRARIA DELL'UNIVERSITÀ DI SASSARI. - ISSN 0562-2662. - 30:(1983), pp. 137-148.
File in questo prodotto:
File Dimensione Formato  
Melis_P_Articolo_1983_Describing.pdf

accesso aperto

Tipologia: Versione editoriale (versione finale pubblicata)
Licenza: Non specificato
Dimensione 447.94 kB
Formato Adobe PDF
447.94 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11388/264075
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact