Diuron Multilayer Adsorption on Activated Carbon from CO2 Activation of Grape Seeds. Issue 1 (2nd January 2016)

• Record Type: Journal Article
• Authors: Bahri, M. Al; Calvo, L.; Gilarranz, M. A.; Rodriguez, J. J.
• Is Part Of: Chemical engineering communications. Volume 203:Issue 1(2016)
• Page Start: 103
• Page End: 113
• Publication Date: 2016-01-02
• Subjects: Activated carbon -- Adsorption -- CO2 physical activation -- Diuron -- Grape seeds; Chemical engineering -- Periodicals; 660.205
• DOI: 10.1080/00986445.2014.934447
• Languages: English
• ISSNs: 0098-6445

Abstract

Abstract : Granular activated carbons were obtained from grape seeds by pyrolysis at 600°C and subsequent physical activation with CO2 (750–900°C, 1–3 h, 25–74% burn-off). The carbon and ash content increased during the activation, reaching values of 79.0% and 11.4%, respectively. Essentially microporous materials with BET surface areas between 380 and 714 m 2 /g were obtained. The performance of the activated carbon in the adsorption of diuron in aqueous phase was studied within the 15–45°C temperature range. Equilibrium data showed that the maximum uptake increased with temperature from 120 to 470 µmol/g, also evidencing some dependence of the adsorption mechanism on temperature. Data were fitted to five isotherm models [Langmuir, Freundlich, Dubinin–Radushkevich, BET, and GAB (Guggenheim, Anderson, and de Boer)]. Kinetic data were analyzed using first- and second-order rate equations and intraparticle diffusion model. The second-order rate constant values obtained (2.8–13.5 × 10 −3 g/µmol min) showed that the hollow core morphology of the material favors the adsorption kinetics.