Study of sepiolite from Goleš (Kosovo, Yugoslavia). II. Acid activation

Abstract

The changes in the pore structure and adsorption properties of sepiolite from Goleš resulting from treatment with 4MHCl for various periods of time were investigated. The BET method specific surface areas, pore volumes and f – plots were determined by nitrogen adsorption. The surface area progressively increased during the 70 hours of acid treatment, when a maximum was attained. The differences in the adsorption properties of the original and the acid treated sepiolite were evaluated by comparison of adsorption isotherms obtained with benzene, n-hexane, methanol and isooctane. The enhanced adsorption of isooctane was of great interest, since the sorption of this compound on natural sepiolites is generally very limited. The results suggest that chemical treatment of sepiolite with 4MHCl for 70 h produces an adsorbent of optimal porosity and other adsorption properties.

Keywords

• sepiolite
• goleš
• acid activation
• surface area
• pore volume
• f – plot
• adsorption