| Abstrakt: |
This study is based on synthesis and characterization of three different clays (Sodic-bentonite noted 𝑁𝑎 − 𝐵𝑡, Dialyl Dimethyl Ammonium Chloride-bentonite noted 𝐷𝐷𝑀𝐴 − 𝐵𝑡 and bentonite intercalated by Hexadecyl Trimethyl Ammonium Bromide or 𝐻𝐷𝑇𝑀𝐴 − 𝐵𝑡. These three clay complexes were characterized by both 𝑋𝑟𝑎𝑦 diffraction (𝑋𝑅𝐷) and Fluorescence (𝑋𝑅𝐹)Scanning Electron Microscopy (𝑆𝐸𝑀), Fourier transform infrared spectroscopy (𝐹𝑇𝐼𝑅), textural measurements (𝐵𝐸𝑇 specific surface areas and porosities) and the cationic exchange capacity (𝐶𝐸𝐶). Corresponding obtained results confirm the good intercalation of the 𝑁𝑎 − 𝐵𝑡 by the two used surfactants at low concentrations (0.006𝑀 for 𝐻𝐷𝑇𝑀𝐴𝐵 and 0.007𝑀for 𝐷𝐷𝑀𝐴+). Obtained results give basal spacing values around 14.5 and 18.5𝐴, respectively for verified two aims firstly: The originality of this research, secondly for minimized the production cost of the adsorbents. Adsorption kinetic study of phosphate ions (𝑃𝑂4 3−) on these three matrices was carried out using kinetic models of pseudo-first, pseudo-second-order and intraparticular diffusion. Results obtained at the studied conditions (room temperature 𝑇 = 25𝑜𝐶), (acidic medium 𝑝𝐻 = 5.7) show clearly the good validity of the pseudosecond-order model which gives a better correlation coefficient both, for 𝐷𝐷𝑀𝐴 − 𝐵𝑡 (𝑅2 = 0.995) and 𝐻𝐷𝑇𝑀𝐴 − 𝐵𝑡 (𝑅2 = 0.999) compared to that obtained by 𝑁𝑎 − 𝐵𝑡 (𝑅2 = 0.990)The aim of this present study was to evaluate the feasibility of using chicken eggshells as low-cost biosorbentfor nickel(II) ions adsorption from aqueous solutions. In order to clarify the adsorption process, batch experiments were performed to study the effect of operating parameters such asbiosorbent dose (1-10 g/L), initial concentration of nickel ions (10-50 mg/L), contact time (5-120 min) and temperature (20-50 °C). To describe the adsorption equilibrium, the experimental data were analyzed by the Langmuir, Freundlich and Temkin isotherm models. The Freundlich model showed better representation of data (R2> 0.999). The maximum adsorption capacity Adsorption isotherms give adsorbed amounts of about 33 and 63 𝑚𝑔. 𝑔−1 onto 𝐷𝐷𝑀𝐴 − 𝐵𝑡 𝐻𝐷𝐷𝑀𝐴 − 𝐵𝑡 complexes, respectively, and 14 𝑚𝑔. 𝑔−1for 𝑁𝑎 − 𝐵𝑡 as reference adsorbent. These results indicated the adsorption of phosphate anions (𝑃𝑂4 3−) by the two prepared Algerian modified organo clays through interactions by the chemisorptions on the surface sites of each used modified clay complexes. [ABSTRACT FROM AUTHOR] |
