Open AccessNatural and Modified Clays for the Removal of Cationic Dye from Water
Author(s) -
Asma Behilil,
Driss Lancene,
Zahraoui Brahim,
Meriem Belhachemi,
Houcine Benmehdi,
Abderrahim ChoukchouBraham
Publication year - 2020
Publication title -
environmental and climate technologies
Language(s) - English
Resource type - Journals
ISSN - 2255-8837
DOI - 10.2478/rtuect-2020-0035
Subject(s) - thermogravimetric analysis , adsorption , calcination , bet theory , cationic polymerization , chemistry , langmuir , langmuir adsorption model , chemical engineering , nuclear chemistry , materials science , organic chemistry , engineering , catalysis
Research and scientific work continue to develop low-cost treatment processes in terms of improving water quality and environmental protection. Oxide of zinc supported in natural clay is synthesized by impregnated method. The role of this modification is to increase the adsorption capacity of a basic dye (Methylene Blue) compared with calcined and natural clays. These samples are characterized by several analytical methods, X-Ray Diffraction (XRD), Thermogravimetric Analysis/Differential Thermal Analysis (TGA/TDA) and Brunauer, Emmett and Teller (BET) theory. The results show that these clays contain three phases, Sericite 2M1, Clinochlore, quartz and the presence of a new phase for the modified clay named zincite. The measured cation exchange capacity (CEC) is 9 cmolc/kg and the BET analysis shows the increase of surface area for these clays, from 9 to 30 m 2 g −1 . The findings show also that the impregnated clay has a better affinity than others when the kinetics data were well fitted by the pseudo-second-order. The adsorption capacities calculated using Langmuir equation of MB onto natural, calcined and impregnated clays are 154.0, 139.6 and 158.1 mg/g, respectively. The thermodynamic data showed that the adsorption of MB on these samples were exothermic. From this study, it can be concluded that these clays are efficacious materials for cationic dye removal from wastewater.