Organophilization of acid and thermal treated sepiolite for its application in BTEX adsorption from aqueous solutions

Acid and thermal treated sepiolite was organophilized by cationic exchange with several alkylammonium cations (octylammonium, hexadecylammonium, tetradecyltrimethylammonium, and hexadecyltrimethylammonium). The adsorption capacity of BTEX from aqueous solutions was evaluated through the adsorption isotherms performed in batch. The results were analysed using three isotherm models: Freundlich, Langmuir and Dubinin-Radushkevich (D-R model). The behaviour of adsorption isotherm suggested the multilayer coverage on a heterogeneous surface, which is according to the Freundlich isotherm model. The thermodynamic analyse using the D-R model show that physical mechanisms govern the process. The maximum adsorption capacity of BTEX on the obtained materials was in the range values of 81.19 mg g(-1) - 1448.42 mg g(-)(1), which are higher than those reported up to now. The organo-sepiolite materials exhibit a high potential in the adsorption of BTEX compounds from aqueous solutions.

Automated summary

Organophilized sepiolite materials synthesized by cationic exchange exhibited high adsorption capacity for BTEX compounds, with Freundlich isotherm model fitting the adsorption behavior well. The thermodynamic analysis using the D-R model indicated that physical mechanisms dominate the adsorption process. The maximum adsorption capacity of BTEX on the obtained materials was within the range of 81.19 mg g(-1) - 1448.42 mg g(-1), which is higher than previously reported values.