Preparation,modification And Properties Of The Derivatives Of Sodium Silicate

In this paper, the derivatives of sodium silicate, including sodium metasilicate pentahydrate, sodium disilicate layered crystal, and silica, were prepared by adjusting the modulus (the molar ratio of SiO2 and Na2O) from the industrial sodium silicate followed by the study on the structure, performance and modification of the derivatives.Sodium metasilicate pentahydrate was prepared by an aqueous crystallization method. The optimized procedure together with the addition of additive was applied to short the crystallization cycle and improve the quality of product. The obtained product was characterized by FTIR, TGA and the measurement of component, showing a quality of product up to superior grade. The preparation ofδ-sodium disilicate layered crystal was conducted by direct calcination of solution of sodium silicate. The structure and morphology of the product were characterized by FTIR, WXRD and SEM and the Ca,Mg ionic exchanging capacity and the anti-acid ability were investigated. The hydrothermal stability of the product was improved through the composite modification of aluminum and CTMAB. Silica aerogel was prepared using drying control agent and atmospheric azeotropic distillation, followed by the characterization of FTIR, WXRD, SEM and BET. A silica aerogel with 2.2 ml/g of pore volume and 779m2/g of surface area was obtained under the optimized process. The wet surface modification in aqueous medium was adopted to modify the filter cake of precipitated silica and the ultrafine silica was obtained and could be dispersed in organic medium. The obtained product was characterized using FTIR, TG, WXRD and SEM followed by the test of hydrohobicity, dispersive capacity and oil absorption value. The effect of the modified conditions and other factors on the quality of product was also studied.