Hydrolysis of δ-Layered Sodium Disilicate in Ions Binding Process

Abstract

Abstract In different type water, the hydrolysis of δ-modification layered sodium disilicate (δ-Na2Si2O5) was investigated by employing XRD, FT-IR, SEM chemical analysis and residual solid yield. δ-Na2Si2O5 was transported to another layered sodium silicate-kanemite (NaHSi2O5·3H2O with cation exchange ability) in distilled water near the concentration in a magnitude, which is used by washing clothing. At the same concentration, δ-Na2Si2O5 changed to a mixture of kanemite, Ca(OH)2 and insoluble amorphous solid in water with Ca2+ cations; a mixture of kanemite and insoluble amorphous solid in water with Mg2+ cations. The evidence which δ-Na2Si2O5 partly transport to another ion exchangeable single layer silicate (kanemite) indicated the existence of cation exchange on δ-Na2Si2O5. Another evidence which δ-Na2Si2O5 partly dissolve and react with Ca2+ and Mg2+ cations indicated the existence to form precipitation. The experimental data suggested that the divalent cation binding process of δ-Na2Si2O5 belongs to a mixture process with divalent cations exchange with Na+ cation and precipitation in form of insoluble amorphous solid.