Equilibrium and kinetic studies of methyl orange and Rhodamine B adsorption onto prepared activated carbon based on synthetic and agricultural wastes

The present study is focused on the valorization of a synthetic (tires) and agricultural (date pit) waste using a simple method in order to obtain an interesting activated carbon, which has been compared with commercial coal. Prepared active carbon is characterized by various techniques such as elemental analysis Brunauer, Emmett and Teller, elementary analysis, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and temperature programmed desorption (TPD). Results of characterization of the two prepared carbons with chemical activation show clearly that a temperature of 550°C and particle diameter of 800 μm give interesting proprieties. The specific surface area reached 770 and 1,030 m2g, respectively, for the different active carbons obtained from tires and date pits. The ratio of carbon in the two prepared activated carbons reached 83% and 93%, respectively for the elementary analysis and surface chemical composition, and the analysis by TPD shows the formation of different functional groups (as radicals, carbonyl groups, and aromatic ethylinique). In order to evaluate the efficiency of these adsorbents, we selected an anionic dye (orange methyl) as a pollutant. Kinetic results show that the adsorption equilibrium is reached at around 60 min with an adsorbed amount of 21.42 and 38.83 mg/g for the tire activated carbon (TAC) and the date pits activated carbon (DPAC) , respectively. The different isotherms were well fitting by the Freundlich model