Interaction of Silicic Acids and Phosphates with Surfaces of Al- and Fe-O-OH-Phases

Dissolved phosphates and silicic acids are absorbed at the surfaces of hydroxide minerals. This may significantly reduce the availability of silicic acid and phosphate in soil and interstitial solutions. Moreover, experimental results display that polymerisation of silica at the surface of solids is favoured at pH = 6. This may appoint a new aspect to the topic, if disordered linked silica molecules within the solution and at the mineral surface promote or inhibit the formation of silicate structures. The affinity of monosilicic acid onto gibbsite and goethite surfaces may be quantified by specific surface complexation constants. The values of the constants are required for modelling of silica adsorption in various natural and technical systems. not assigned GG: Industrielle Förderung