Kinetics of the alteration of K-feldspar in buffered solutions at low temperature

A study has been made of the release of Si and Al to solution from the alteration of a potassic feldspar in solutions buffered at pH values between 4 and 10. Release of both Si and Al is consistent with diffusion from an altered layer, presumably formed by rapid initial hydration and exchange of H+ for K+. In a limited volume of solution diffusion ceases when the Al concentration in the external solution reaches a fixed value at each pH; this value is reasonably consistent with the solubility of Al(OH)3. The Si concentration tends to reach a maximum at each pH. The interpretation is made that the maximum in Si concentration corresponds to a balance between Si diffusion into the solution, and Si removed from the solution by reaction with Al(OH)3 to form a hydrated silicate. The calculated equilibrium value for the reaction Al(OH)3 + SiO2aq = Al-silicate is 5 ppm SiO2. © 1967.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Aspect chimique du mode de formation des bauxites dans le Bas-Congo

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Etude du mécanisme de polymérisation des hydrocarbures dans la synthèse Fischer-Tropsch. Première partie: Texte. Deuxième partie: Figures[. Un seul volume]

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Methodology of research in micropollutants - heavy metals

A comparison of the concentration of dissolved and of particulate heavy metals in the aquatic system indicated that these elements are strongly enriched in the suspended matter. The transfer between the aqueous phase and the solid phase may be due to dissolution-precipitation reactions, adsorption-desorption processes or biological processes. When these processes are identified, is is further possible to develop mathematical models which describe the behaviour of these elements. The enrichment of heavy metals in the particulate phase suspended or deposited and in aquatic organisms constitutes a powerful tool in order to evaluate sources of pollution.SCOPUS: NotDefined.jinfo:eu-repo/semantics/publishe

Kinetic study of the dissolution of albite with a continuous flow-through fluidized bed reactor

info:eu-repo/semantics/publishe