Adsorption of dyes from aqueous solution onto activated carbons prepared from date pits: The effect of adsorbents pore size distribution

Abstract

Several active carbons were prepared starting from Algerian date pits by chemical activation with the ZnCl2, by physical activation with the CO2, and by a method combined in the presence of ZnCl2/CO2. The active carbons obtained were followed by the evaluation of the yield and the physisorption of nitrogen at 77 K. Activated carbon particles were analyzed by scanning electron microscope (SEM). Indeed, it showed that mesoporous active carbon can be obtained at a lower cost by chemical impregnation in ZnCl2 with 800°C followed by activation with CO2. Thus, techniques combining the chemical method (ZnCl2) and the physical method (CO2) help to widen the pores allowing the conversion of the micropores into mesopores. Dye contamination in wastewater can lead to a variety of environmental problems. Colored water can affect plant life and thus an entire ecosystem can be destroyed by contamination of various dyes in water. The produced AC was tested against methylene blue and Congo red. This test was conducted to check the ability of the produced activated carbon. The mesoporous carbons showed high adsorption capacity of methylene blue and Congo red.