Application of Tunisian limestone material for chlorobenzene adsorption: characterization and experimental design

Abstract

This study has been undertaken to the optimization of chlorobenzene adsorption of onto carbonate material outcropping in Tataouine region located in Southern Tunisia. Response surface methodology was adopted as a tool for the experimental design; A Hoke D6 experimental design model was applied. In order to improve the adsorption capacity of raw material, different adsorbents were prepared by addition of three salts (Na 2 SO 3 , NaCl and Na 2 SO 4 ) and then heated to 300, 450 and 600°C. The obtained results indicated that the studied samples were mainly composed of calcite. Temperature and salt concentration were the most controlling factors in activation process. Optimum adsorption conditions were obtained for 5 % of NaCl as activation salt and 450°C of activation temperature of carbonate samples. The activated carbonate showed an increase in its porosity (8 to 58.35 %) and surface area (2-14.6 m 2 g −1 ). Moreover, chlorobenzene adsorbed amount showed an enhanced value, varying from 30 to 120 mg g −1 at 25°C.