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Synthesis of activated carbon from spent tea leaves for aspirin removal

Wong, Syieluing and Lee, Yowjeng and Ngadi, Norzita and Inuwa, Ibrahim Mohammed and Mohamed, Nurul Balqis (2018) Synthesis of activated carbon from spent tea leaves for aspirin removal. Chinese Journal of Chemical Engineering, 26 (5). pp. 1003-1011. ISSN 1004-9541

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Official URL: http://dx.doi.org/10.1016/j.cjche.2017.11.004

Abstract

Adsorption capacity of activated carbon prepared from spent tea leaves (STL-AC) for the removal of aspirin from aqueous solution was investigated in this study. Preliminary studies have shown that treatment with phosphoric acid (H3PO4) increased removal efficiency of STL-AC. Characterizations on STL-AC revealed excellent textural properties (1200 m2·g− 1, 51% mesoporosity), as well as distinctive surface chemistry (1.08 mmol·g− 1 and 0.54 mmol·g− 1 for acidic and basic oxygenated groups, pHpzc = 2.02). Maximum removal efficiency of aspirin observed was 94.28% after 60 min when the initial concentration was 100 mg·L− 1, 0.5 g of adsorbent used, pH 3 and at a temperature of 30 °C. The adsorption data were well fitted to the Freundlich isotherm model and obeyed the pseudo-second order kinetics model. The adsorption of aspirin onto STL-AC was exothermic in nature (ΔHϴ = − 13.808 kJ·mol− 1) and had a negative entropy change, ΔSϴ (− 41.444 J·mol− 1). A negative Gibbs free energy, ΔGϴ was obtained indicating feasibility and spontaneity of the adsorption process. The adsorption capacity of AC-STL (178.57 mg·g− 1) is considerably high compared to most adsorbents synthesized from various sources, due to the well-defined textural properties coupled with surface chemistry of STL-AC which favors aspirin adsorption. The results demonstrate the potential of STL-AC as aspirin adsorbent.

Item Type:Article
Uncontrolled Keywords:Activated carbon, Adsorption
Subjects:T Technology > TP Chemical technology
Divisions:Chemical and Energy Engineering
ID Code:84374
Deposited By: Widya Wahid
Deposited On:28 Dec 2019 09:55
Last Modified:28 Dec 2019 09:55

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