Adsorption of Nicotine on Calcinated and Modified Compressed Coffee Residue CACS and Its Surface Properties

Document Type : Original Article

Authors

1 Department of Chemistry, Faculty of Sciences, Damascus University, Syria.

2 Department of Chemistry, Faculty of Sciences, Damascus University, Syria

3 Department of Chemistry, Faculty of Sciences, Damascus University, Syria\ Syrian Private University, Damascus, Syria.

Abstract

A dried compressed coffee residue was calcinated at the temperature of 400 0C for 4 hours. It was analyzed quantitatively and qualitatively by using the X-Ray Fluorescence (XRF) spectroscopy. The coffee carbon surface was modified with oleum. The surface properties of the sample was studied by using the FTIR spectroscopy after each treatment resulting new different peaks that indicate the modification with oleum. Besides, other peaks that indicate the adsorption of nicotine on its surface were obvious. The concentrations of nicotine in the studied solutions were measured by using the spectrophotometry, the nicotine adsorption on the studied adsorbent followed the pseudo second-order model. The effect of nicotine concentration was also studied at the temperatures of 20- 30- 35- 40 0C; an increasing of the nicotine adsorption was noticed with the increasing of the initial concentration at each of the studied temperatures; the adsorption curves fitted the Langmuir and Freundlich isotherms models. In addition, the thermodynamic parameters of the surface adsorption interaction ∆G0, ∆H0, ∆S0 were determined, the resulting values showed that the interaction is endothermic and the adsorption is of chemical nature. Besides, a mechanism for the adsorption of nicotine on modified compressed coffee residue carbon (CACS) was suggested presuming the participation of the two nitrogen atoms in the polar nicotine molecule.

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