ISSN:
1435-1536
Schlagwort(e):
Critical coagulation concentration
;
iron (III) hydroxide sol
;
silver iodide sol
;
sedimentation
;
Hamaker constant
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
Notizen:
Abstract A method for determining the critical coagulation concentration (C c) from the change in the transmittance of the sol with stand time after adding a coagulating agent is discussed. Potassium nitrate was used as the coagulating agent because the specific adsorption of electrolyte ions on the particle and the hydrolysis of electrolyte ions are negligible. Apparent critical coagulation concentrations,C c a, of iron (III) hydroxide and silver iodide sols were obtained from the transmittance vs. potassium nitrate concentration curves for various stand times. The values ofC c a decreased with increasing stand time. TheC c a value obtained for the shortest stand time was closer toC c obtained from the initial turbidity change of the sol by applying Rayleigh's law. The Hamaker constant for the particle in water was calculated from theC c a value obtained at the shortest time and the experimentally determined outer Helmholtz plane potential. The calculated Hamaker constants were comparable to the theoretical values for iron (III) hydroxide and silver iodide.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00657675
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