Journal
JOURNAL OF HAZARDOUS MATERIALS
Volume 135, Issue 1-3, Pages 226-231Publisher
ELSEVIER
DOI: 10.1016/j.jhazmat.2005.11.056
Keywords
adsorption; bentonite; stearic acid; thermodynamic parameters
Categories
Ask authors/readers for more resources
Adsorption equilibrium of stearic acid onto natural bentonite with Turkish origin was studied at the temperatures of 298, 308 and 318 K. SEM and XRD analysis show that the bentonite used as adsorbent is composed of microcrystal and porous structure. The specific surface area was determined by BET method as 38.6 m(2)/g. The adsorption of stearic acid onto bentonite was conformed to the Langnmuir and Freundlich isotherms. The equilibrium parameter, R-L revealed that the bentonite is a good adsorbent for stearic acid. The sorption capacity of bentonite studied decreases with increasing temperature. However, it is concluded that the adsorption capacity of bentonite for the stearic acid under the same experimental conditions is in comparable level in terms of that of the rice husk ash given in literature. Thermodynamic parameters, Delta G degrees(ads), was calculated to be between -21.8 and -22.8 kJ mol(-1). Delta H degrees(ads) and Delta S degrees(ads) were found to be -9.2 kJ mol(-1) and 42.4 J mol(-1) K-1, respectively. These parameters obtained as a function of temperature indicate that the adsorption of stearic acid onto bentonite was a spontaneous and an exothermic process. An FT-IR study on the adsorbed material was used to verify the interaction of the stearic molecule with bentonite after adsorption process. (c) 2005 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available