Publications Internationales
Permanent URI for this collectionhttps://dspace.univ-boumerdes.dz/handle/123456789/13
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Item Extractive dearomatization, denitrification and desulfurization of gas oil fractions by a mixed extractant of N,N-methylpyrrolidone, N,N-dimethylformamide and ethylene glycol via microwave radiations(Taylor & Francis, 2019) Mesdour, Souad; Boufades, Djamila; Moussiden, A.; Hamada, B.In an attempt to develop alternative process that meet the prescribed levelsand green-technology criteria in gas-oil refining, N,N-methylpyrrolidone(NMP), dimethylformamide (DMF) mixed solvents under microwave-radiations (MW) were tested for the gas-oil desulfurization (EDS), denitrifica-tion (EDN) and dearomatization (EDA). In optimal conditions the gas-oilEDS-efficiency via MW can reach as high as 99.1% within 5 min at 500W inthree stages, which is much higher than EDS without MW (88.5% within15 min) or than those of ionic liquids. The NMP/DMF/EG can be reused formulti-cycles before being regenerated by adsorption method. This study willprovide useful information for future industrial applicationItem Removal of heavy metal ions by adsorption onto activated carbon prepared from Stipa tenacissima leaves(Taylor & Francis, 2017) Madani, N.; Bouchenafa-Saib, N.; Mohammedi, O.; Varela-Gandíac, F.J.; Cazorla-Amorós, D.; Hamada, B.; Cherifi, OuizaItem Synthèse du benzo-1,4-dioxanne en catalyse par transfert de phase = Synthesis of 1,4-benzodioxan by phase transfer catalysis(1994) Hamada, B.; Kaddour, O.; Safar, M.; Boukherissa, A.La synthèse du benzo-1,4-dioxane par interaction du 1,2-dichloroéthane avec le pyrocatéchol a lieu en présence de solvants polaires qui sont parfois très coûteux. Dans ce travail, la réaction de synthèse a été améliorée du point de vue vitesse et rendement par l'utilisation de la catalyse par transfert de phaseItem Study of retention of organophosphorus compoundsand volatile organic solventson polydimethylsiloxane using inverse gas chromatography(Metody i Ob'ekty Khimicheskogo Analiza, 2013) Ihdene, Z.; Mekki, A.; Bekkar; Sayah, A.R Djelloul; Kapitanov, I.V.; Karpichev, E.A.; Hamada, B.A detailed study of retention of the variety of volatile organic solvents (VOS) and organophosphorus compounds on the polydimethylsiloxane (PDMS) preliminary characterized by FTIR and DSC methods was carried out by means of an inverse gas chromatography technique. The specific retention volumes and infinite dilution activity coefficients were determined for different classes of VOCs, linear and cyclic alkanes, chloroalkanes, oxygen compounds (alcohols, ketones, and esters), and nitriles as well as for typical organophosphorus compounds, 4-nitrophenyl esters of diethyl phosphoric (paraoxon) and diethyl thiophosphoric (parathion) acids. The effect of dipole-dipole interactions and dispersion interactions on the efficacy of the retention of the studied compounds on the PDMS was analyzed. Organophosphorus stimulants are characterized by strong retention on the PDMS, the difference in their retention are to be connected with more efficient dipole-dipole interaction of the oxygen atom of paraoxon with the PDMS than that of the sulphur atom of parathion. A possibility of using PDMS as a base for the detection layers sensitive to organophosphorus compounds was demonstratItem Liquid–liquid extraction and quantitative determination of tungsten (VI) using macrocyclic reagent (DB-18-C-6) as a thiocyanate complex [WO (SCN)5]2(Taylor & Francis, 2014) Nabiev, M.; Hamada, B.; Nabieva, A. M.; Amrane, A.; Nasrallah, N.; Saoud, A.In recent years, the extraction using crown ethers has reached a resounding success in different scientific and technical fields. In this work, the authors report the results of the main steps of extraction and determination (proportioning) of the tungsten ion (VI) using a chloroformed solution of crown ether. The dibenzo–18–C-6(2,3,11,12-dibenzo-1,4,7,10,13,16-hexaoxacyclooctadeca- 2,11-diene according to the IUPAC systematic nomenclature). The identification and quantification of W(VI) using the absorption spectrum, the influence of the necessary reagents, the needed acidity level for complete extraction and complexation of W (VI) using a crown ether, and the influence of multivalent metal ions were examined, considering that the sensitivity, selectivity, and detection limits have been determined. This system obeys Beer’s law in the range of 0.18–18.3 lgcm 3of tungsten with a molar absorption of 1.6 104 mol 1 cm 1 at 415nm and the detection, quantification limits were, respectively, equal to 0.7–1.8 lgcm 3. The developed method was applied for the extraction of W(VI) in the high speed steel (HSS): HS2–9-1–8 containing 2% W, 9% Mo, 1% V, and 8% CItem Isomérisation du m-xylène sur la zéolithe synthétisé NaX : optimisation des paramètres et étude cinétique du processus réactionnel(2005) Chemat, Z.; Gourine, N.; Nabiev, M.; Hamada, B.La réaction de l'isomérisation du m-xylène sur la zéolithe synthétisé de type NaX et dont la forme sodique a été changé en utilisant l'ammoniaque afin d'accéder à sa forme protonique (acide) qui est la forme active pour catalyser cette réaction. On obtient un mélange de xylènes (méta-, orto- et para-xylène) ainsi que quelques produits secondaires issues des réactions de transalkylation (toluène, triméthylbenzènes,...). une étude cinétique ainsi qu'une optimisation du rendement en ortho- et para-xylène ont été réaliséItem Atmospheric pressure microwave assisted heterogeneous catalytic reactions(2007) Chemat-Djenni, Z.; Hamada, B.; Chemat, F.The purpose of the study was to investigate microwave selective heating phenomena and their impact on heterogeneous chemical reactions. We also present a tool which will help microwave chemists to answer to such questions as “My reaction yields 90% after 7 days at reflux; is it possible to obtain the same yield after a few minutes under microwaves?” and to have an approximation of their reactions when conducted under microwaves with different heterogeneous procedures. This model predicting reaction kinetics and yields under microwave heating is based on the Arrhenius equation, in agreement with experimental data and procedures