Characterization of Hydrophobic Nature of High Siliceous Zeolite-Silicalite by Adsorption and Diffusion
Abstract
Silicalite samples with Si/Al ratios of 126, 563, and 1062 were characterized in terms of adsorption and diffusion with water, methanol, benzene and n-hexane at 25 C. The characterization was carried out by the gravimetric method with a Cahn electro-balance in a constant-volume and constant-temperature system. It was found that (1) the saturation equilibrium adsorption capacity for water in silicalite decrease as the Si/Al ratio increases; (2) the effect of Si/ Al ratio on the saturation equilibrium adsorption capacity of organics in silicalite is small; and (3) the diffusion of guest molecules in silicalite depends primarily on the size of the guest molecules. Additionally, a comparison of hydrophobic properties of silicalite and activated carbon was made. The result indicates that the water adsorption capacity of silicalite is about twelve times less than that of activated carbon. Hydrophobicity of silicalite increases substantially after fluorination (F-silicalite). Keywords: Hydrophobicity; Aluminum; Silicalite; Zeolite; Silica; Adsorption; Diffusion; Methanol; Benzene; Hexane.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1988
- Accession Number
- ADA199636
Entities
People
- Chen C. Hsu
- Yi H. Ma
Organizations
- Edgewood Chemical Biological Center