@article {1848, title = { High adsorption capacity of nitrobenzene from aqueous solution using activated carbons prepared from vegetable waste }, journal = { ENVIRONMENTAL PROGRESS \& SUSTAINABLE ENERGY }, year = {2020}, abstract = {

The present study reports the preparation of chemically activated carbons (PAC and ZAC) from apricot stones using phosphoric acid and zinc chloride, respectively. The potential use of the prepared carbons, as adsorbents, and the effect of chemical activation on the surface properties and adsorptive mechanism of nitrobenzene (NB) were investigated. The physicochemical properties of the obtained materials were characterized by Nitrogen adsorption-desorption isotherms, Scanning Electron Microscope, FTIR Spectroscopy, EDX analysis, Boehm titration, and pH of zero charge. The results show that the prepared samples present high apparent surface areas (1,382 and 1,111 m(2)/g for PAC and ZAC, respectively) and pores volumes with the presence of various functional groups. It was found that pseudo-second model was the most suitable for the fitting of the experimental kinetic data and the intraparticle diffusion was not the unique rate-controlling stage. The adsorption isotherms were well described by the Langmuir and the Freundlich models. According to the Langmuir model, the maximum adsorption capacity of PAC and ZAC were about 476.2 and 490.2 mg/g, respectively. The thermodynamic parameters showed the spontaneity, the exothermic nature, and the decrease in the randomness of the adsorption of nitrobenzene. Chemical regeneration showed that the prepared samples could be used for four time desorption-adsorption cycles with good efficiency for NB removal, indicating that the prepared carbons could be used as a low-cost alternative to commercial activated carbon for the removal of nitrobenzene from wastewater.

}, author = {Z. KECIRA and O. BENTURKI and A. BENTURKI and M. DAOUD and P. GIRODS} } @article {1663, title = { Removal of reactive dye (BEZAKTIV Red S-MAX) from aqueous solution by adsorption onto activated carbons prepared from date palm rachis and jujube stones }, journal = { JOURNAL OF MOLECULAR LIQUIDS }, volume = {243}, year = {2017}, pages = {799-809}, abstract = {

In this study, activated carbons were prepared from date palm rachis (RPK) and jujube stones (NJK), by-product agricultural wastes which have been tested for the elimination of reactive dye BEZAKTIV Red S-MAX (BRSM) from aqueous solutions by batch adsorption method. Both activated carbons were prepared using chemical activation by KOH as an impregnating agent (rate of KOH/biomass (w/w) of 0.74) at 800 degrees C in the presence of inert gas (N-2). RPK and NJK were characterized using BET, SEM, FTIR and Boehm titration mass. The results show that RPK possess the higher specific surface area (1160 m(2)/g). The effect of contact time, solution temperature and solution pH on the adsorption of BRSM dye were also studied. The experimental data were analysed using Langmuir, Freundlich and Temkin isotherm models. The equilibrium data fitted well with the Langmuir isotherm model, and the adsorption capacities were calculated to be 12821 and 28.49 mg/g using RPK and NJK, respectively. The kinetic data were fitted to pseudo-first order, pseudo-second order, elovich and intra-particle diffusion model. Thermodynamic parameters such as Delta G degrees, Delta H degrees and Delta S degrees were also estimated for the adsorption study and they were found to be spontaneous and endothermic processes. Desorption and regeneration study was made to test the viability of reusing the adsorbents. Lastly, it was found that RPK is efficient in dyes removal from real wastewater.

}, url = {https://hal.archives-ouvertes.fr/hal-01644031}, author = {M. DAOUD and O. BENTURKI and Z. KECIRA and P. GIRODS and A. DONNOT} } @article {1546, title = {The use of an agricultural waste material from Ziziphus jujuba as a novel adsorbent for humic acid removal from aqueous solutions}, journal = {JOURNAL OF MOLECULAR LIQUIDS}, volume = {211}, year = {2015}, pages = {1039-1046}, abstract = {

The purpose of our work is the development of a local agricultural waste biomass material, Ziziphus jujuba known as Nebka (NB), into activated carbons to remove humic acid (HA) from aqueous solutions. This was further treated with nitric acid solutions. The surface characteristics of the adsorbent were calculated using the standard Brunauer-Emmet-Teller method (BET). The microstructures of the samples were observed with scanning electron micrographs. Chemical characterization of the samples was carried out by selective titrations and Fourier Transform Infrared Spectroscopy (FT-IR). On the basis of the BET results, we have obtained the best microporous activated carbon oxidized (surface area of 970 m(2)/g, microporous volume of 0.170 cm(3)/g and total pore volume of 0326 cm(3)/g). Adsorption studies were conducted using a batch process, to study the effects of contact time, pH and temperature. The pH dependent sorption of HA was found maximum at pH range 4-6 for an initial concentration of 50 mg/L. The equilibrium adsorption data was analyzed using Langmuir and Freundlich isotherm models, and the kinetic data was analyzed using pseudo-first order and pseudo-second order kinetic models. The equilibrium data were well fitted to the Freundlich isotherm. The adsorption reached equilibrium after 300 mm and the maximum adsorption capacity was about 76.92 mg/g at 20 degrees C according to the Langmuir model. The adsorption kinetic was found to follow the pseudo-second-order kinetic model. Thermodynamic study showed that the adsorption of HA onto oxidized activated carbons was feasible, spontaneous and endothermic at 20-40 degrees C.

}, url = {https://hal.archives-ouvertes.fr/hal-01269501}, author = {H.D. BOURAS and O. BENTURKI and N. BOURAS and M. ATTOU and A. DONNOT and A. MERLIN and F. ADDOUN and M.D. HOLTZ} }