The Extraction Fraction of Al₂O₂ & SiO₃ by Acid & Alkali in Allophanes

Abstract

Allophane is a special kinds of clay mineral widely distributed in Japan, this is itself hydrated amorophous aluminium silicate gel. The Si0₂/Al₂0₃ of allophane depends on the producing place.
The charactristic of Terauchi-do was studied by H. Tanaka. But Kisodo, Kitakami-do and Osawa-do are not studied. So, these allophanes were studied dissolution charactristic in liquid phase by NaOH solution, physical properties, analysis by Infrared spectroscopy & X-ray, the effect of Si0₂/Al₂O₃ mol. ratio in allophane and chemical composition of these allophanes on synthesis of zeolite.
The result, these allophanes showed the special dissolution charactristic. The extraction fraction of alumina in allophane increased with treating time becoming longer. But, the treating time becoming longer, the extractive fraction of silica in allophane increased temporarily and then decreased rapidly. This charactristic can be estimated originating in the action of Si0₂ & Al₂0₃ in liquid phase and synthesizing of zeolite.