Adsorption of Cu(II) ions from aqueous solutions on biochars prepared from agricultural by-productsAdsorption of Cu(II) ions from aqueous solutions on biochars prepared from agricultural by-products Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2015-11-012011enIn this study, the adsorption of Cu(II) from aqueous solutions by agricultural by-products, such as rice husks, olive pomace and orange waste, as well as compost, was evaluated. The aim was to obtain sorbent materials (biochars) through hydrothermal treatment (300 °C) and pyrolysis (300 °C and 600 °C). The effect of adsorbent dose, pH, contact time and initial Cu(II) concentration in batch-mode experiments was investigated. The optimum Cu(II) adsorption conditions was found to occur at 5-12 g/L adsorbent dose, initial pH 5-6, and reaction time 2-4 h. Furthermore, the adsorption kinetics were best described by the pseudo-second order model for all the tested materials, while the adsorption equilibrium best fitted by the linear and Freundlich isotherms. Comparing rice husks and olive pomace, the higher adsorption capacity resulted after pyrolysis at 300 °C. With respect to the orange waste and compost, the highest adsorption capacity was observed using biochars obtained after hydrothermal treatment and pyrolysis at 300 °C.http://creativecommons.org/licenses/by/4.0/Journal of Environmental Management96135-42 Pellera Frantseska-Maria Πελλερα Φραντσεσκα-Μαρια Giannis Apostolos Kalderis Dimitrios Καλδερης Δημητριος Anastasiadou Kalliopi Stegmann, Rainer Wang Jing-Yuan Gidarakos Evaggelos Γιδαρακος Ευαγγελος Elsevier Cu(II) adsorption Agricultural by-products Hydrothermal Pyrolysis