Publications Internationales

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    A review of emulsion flows, their characterization and their modeling in pumps
    (Institution of Chemical Engineers, 2024) Achour, Lila; Specklin, Mathieu; Asuaje, Miguel; Kouidri, Smaine; Belaidi, Idir
    In the engineering field, emulsions and liquid–liquid two-phase flows within centrifugal pumps are generally unwanted as emulsions will have negative effects on pump operation. Besides, emulsions are usually formed when the oil and water phases are brought together in a process called emulsification, which is enhanced by high shear rates. This topic has been extensively researched over the past decades, with sophisticated theories regarding the phenomena involved in emulsions formation and characterization in pumps. Besides, given the complexity of the physics governing emulsions, studies on their modeling within pumps, based on empirical correlations or computational fluid dynamics models, are insufficient and remain limited. This review aims to provide a complete overview of investigations on liquid–liquid flow in centrifugal pumps. Characteristics of these mixtures, such as stability, phase inversion, droplet size distribution and rheological behavior, are discussed. Current approaches and techniques for analyzing pump performance handling emulsion and two-phase liquid–liquid flow are reviewed thoroughly. The limitations of the existing models are studied, and potential future developments are proposed.
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    A novel spherical hybrid material based on the combination of humic acid/alginate/Algerian Zeen Oak sawdust for removing chromium (VI) from wastewater
    (Elsevier, 2023) Sadoun, Louiza; Benmounah, Abdelbaki; Ait-Ramdane-Terbouche, Chafia; Seffah, Karima; Terbouche, Achour
    A novel spherical hybrid material designed from the combination of humic acid (HA), sodium alginate (Al) and sawdust derived from Algerian Zeen Oak Waste (OS) has been prepared. After optimization of HA/Al/OS mass ratio, the structure of the synthesized hybrid spheres was established using various characterization techniques notably ATR, SEM-EDX, XRD, BET and the point of zero charge (pHpzc). Adsorption tests using this compound were applied to remove chromium(Cr (VI)) from aqueous solutions. The influence of the different parameters such as contact time, pH, temperature, initial metal concentration, and mass of the material were studied. The obtained results revealed that the mass of HA had a significant influence on the formation of the spheres. By varying the ratio of HA/Al/OS (1/16/16 (S1), 1/5/5 (S2), 1/3/3 (S3) and 1/2/2 (S4)), the humic acid allowed a good coating of the hybrid material. The ratio 1/5/5 (S2) was retained for the adsorption study. The efficiency of this material was subsequently tested for the removal of Cr (VI) from aqueous solutions. Optimizing the different experimental parameters allowed to obtain a removal efficiency of over 90 % for an initial Cr (VI) concentration of 60 mg L−1, at pH = 2 and temperature of 353.15 K, using 0.1 g of material. The kinetic study showed that the process of elimination of Cr (VI) followed the pseudo-second order model and well fitted with the Freundlich adsorption isotherm model with R2 value of 0.99 and a low value of χ2 (2.88). A maximum adsorption capacity of 50.328 mg.g−1 was determined by the Langmuir isotherm model. The hybrid spheres showed good regeneration efficiency even after four adsorption-desorption cycles. The thermodynamic study (ΔS = 0.091 kJ mol−1 K−1, ΔH = 24.427 kJ mol−1 and ΔG° = −2.883 kJ mol−1 at 298.15 K) revealed that the adsorption process was spontaneous, favorable and endothermic with a physisorption phenomenon. Finally, the adsorbent was successfully applied to real wastewater contaminated with chromium. This application has proved high removal efficiency of Cr (VI) and a yield of 94.31 % was obtained at 40 °C.
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    Synthesis, characterization and application of tetragonal BaTiO3-δ in adsorption and photocatalysis of congo red
    (Elsevier, 2023) Merrad, S.; Abbas, Moussa; Brahimi, R.; Bellal, B.; Trari, M.
    The synthesis by a simple approach of the deficient Barium Titanate BaTiO3-δ (BTO) crystallizing in a perovskite structure is reported along with the physicochemical properties. Thermal analysis (TG/DSC) was performed to elucidate the synthesis process. The X-ray diffraction (XRD), BET analysis, scanning electron microscopy (SEM-EDS) and electrochemistry were investigated. The catalyst revealed a single phase with a tetragonal symmetry obtained by treatment at 650 °C. The direct band gap (3.34 eV), obtained from diffuse reflectance spectroscopy (DRS), is assigned to the charge transfer O2-: 2p-Ti4+: 3d. The electrical characterization indicated a non-degenerate conductivity due to oxygen vacancies with an activation energy of 0.33 eV. The capacitance measurements indicated n-type behavior with a flat band potential (Efb) of − 0.43 V and a carrier concentration (ND) of 3.90 1018 cm−3. The photocatalytic process was elucidated by the electrical impedance spectroscopy (EIS). The performance of BTO was assessed by a combination of the adsorption of Congo Red (CR) followed by its degradation under UV light. The photodegradation kinetic was well fitted by a pseudo-first-order model with an abatement of 50% and 91% under UV and solar lights respectively. Different scavengers were used to evaluate the reaction mechanism and the radicals O2•- are the main reactive species of the CR oxidation. Four regeneration cycles demonstrated the catalyst stability. A degradation mechanism was established based on the scavengers effect
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    Chemical characterization of asphaltenes deposits from Hassi Messaoud field
    (Elsevier, 2022) Behnous, Dounya; Bouhadda, Youcef; Moffatt, Brian; Zeraibi, Noureddine; Coutinho, João A.P.
    The precipitation and deposition of asphaltenes are complex phenomena that reduce the efficiency in oil production operations. In this study, spectroscopic and thermal methods were used for the characterization of asphaltene samples extracted from deposits belonging to different locations in the Hassi Messaoud field. Structural parameters and the chemical structure of the studied asphaltenes were determined using 13C solid nuclear magnetic resonance (NMR), X-ray diffraction and Raman spectroscopy. The thermal behavior of the asphaltenes studied was examined using differential scanning calorimetry. The results obtained suggest that island is the predominent architecture for the asphaltenes studied with an average of 7 to 8 fused rings and aliphatic length chain of about 3–4 carbons. The number of aromatic sheets in a stacked cluster (N) is between 7 and 8 sheets. The aromatic sheet diameter of the four samples ranges from 12.18 to 15.52 Å with an average interlayer distance between aromatic sheets of 3.52 Å and an average interchain layer distance of 4.48 Å
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    Application of Fourier Transform Infrared (FT-IR) Spectroscopy to the Study of the Modification of Epoxidized Sunflower Oil by Acrylation
    (Sage journals, 2012) Irinislimane, Ratiba; Belhaneche-Bensemra, Naima
    Commercial sunflower oil was epoxidized at the laboratory-scale. The epoxidized sunflower oil (ESFO) was modified following the acrylation reaction. Modification was carried out simultaneously using acrylic acid (AA) and triethylamine (TEA). To optimize the reaction conditions, the effects of four temperatures (40, 60, 80, and 100 °C), the ESFO:AA (100:100) ratio, and 0.2% TEA were investigated. The rate of conversion was analyzed with both FT-IR and titration of the oxirane ring. After that, the temperature with the highest conversion was selected and used throughout for all modification reactions. Then, four ratios (100:100, 100:90, 100:80, and 100:75) of ESFO:AA were analyzed at four different concentrations of TEA (0.2, 0.3, 0.4, and 0.5%) to determine the best estimate for both the ESFO:AA ratio and the catalyst concentration. Conversion rate was analyzed using FT-IR spectroscopy by measuring the concentrations of ester, carbonyl, and alcohol groups. Moreover, oxirane***ring concentration was estimated using the titration method (with gentian violet as indicator) and FT-IR spectroscopy (epoxy ring absorptions at 1270 cm−1 and 877 cm−1). Based on conversion yield, the optimum ESFO:AA ratio corresponds to 100:80; the best temperature reaction was at 60 °C, and the best TEA concentration was 0.2%. The critical amounts of reactants needed to reach maximum conversion were established. The final acid value of the acrylated ESFO after washing (pH = 7) was 2.1 mg potassium hydroxide (KOH) g−1. All results show that FT-IR spectroscopy is a simple, low-cost, rapid method for investigating the kinetics of a reaction
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    Characterization of the interface of a Non-Ferrous dissimilar realized by rotary friction welding
    (Springer, 2021) Mebtouche, A.; Bezzazi, Boudjema; Ramou, N.; Aboudi, D.; Faci, Y.; Latef, M.
    The need for assembly between dissimilar materials often arises in complex industrial applications. It avoids problems inherent in conventional welding. Therefore, in this study the performance of welded joints developed using a rotary friction welding machine, between Cu/Al, are characterized. The interface of the welded assembly of dissimilar copper Cua1 and AA2014 aluminum, consists of several intermetallic compounds mainly CuAl2, CuAl and Cu9Al4. Dendrites have been revealed, this structure is known to be the result of solidification. While rotary friction welding is done at the solid state. In this work, we seek to know the phenomena that take place during the entire process and in the creation of the interface. This article presents the study of the Al/Cu interfacial structure of welded joints made by rotary friction in a modified cycle with two steps
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    Seismic attributes in reservoir characterization: an overview(Review)
    (Springer link, 2021) Oumarou, Sanda; Djeddi, Mabrouk; Tabod Charles, Tabod; Jean, Marcel; Ngos III, Simon; Jean Marcel, Abate Essi; Kamguia, Joseph
    The present study focuses on a literature review using seismic attributes in the characterization of hydrocarbon reservoirs. This work consists of examining the contribution of seismic attributes in the characterization of reservoirs. With this, it is necessary to identify and list the attributes involved in analyzing the reservoirs and their degree of involvement in the characterization of the hydrocarbon accumulation zones. The approach used is to classify attributes according to their levels of intervention as the attributes that circumscribe hydrocarbon accumulation zones such as instantaneous frequencies. Thus, the attributes which make it possible to analyze the seismic facies must be enumerated to determine the type of hydrocarbons. The aim of this work is not only to review the literature on the use of seismic attributes in the characterization of reservoirs but also to expose the limitations of these attributes in the study of reservoirs to search for the most adapted attributes that have never been used in reservoir analysis. As a result, several seismic attributes used in reservoir characterization will be evaluated while demonstrating their strengths and limitations to consider either the combination of certain attributes or the experimentation of new attributes in deepening the knowledge on the study of reservoirs. This work will contribute to a more sophisticated study in this domain
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    Modeling of porosity by geostatistical methods
    (Springer, 2019) Ketteb, Rachid; Djeddi,Mabrouk; Kiche,Yacine