Surface Fractal Analysis of Silica Gel by Using Adsorption Data

Abstract

Abstract: The surface fractal dimension Dof a mesoporous silica gel were determined by adsorption method.The method is based on the adsorption isotherms of formic, acetic, propionic acids and carbon tetrachloride vapours on the silica gel, and adsorption isotherms of normal aliphatic alcohols from dilute carbon tetrachloride solutions by the silica gel.The obtained fractal dimension Dvalues are similar values to those obtained by using some other method, which are close to two(D=2.06+0.05).But the Dvalue determined by adsorption data in the capillary condensation reigime CCl₄vapour is lower than 2 The low Dvalues can be explained in terms of the characteristic the porour structure of the silica gel.

Key words: Fractal surface, Fractal dimension, Silica gel, Adsorption

CLC Number:

O647
O189

TrendMD:

ZHAO Zhen-Guo . Surface Fractal Analysis of Silica Gel by Using Adsorption Data[J]. Chem. J. Chinese Universities, 2003, 24(11): 2051.

References

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