فهرست مطالب

Iranian Journal of Chemistry and Chemical Engineering
Volume:39 Issue: 5, Sep-Oct 2020

  • تاریخ انتشار: 1399/09/19
  • تعداد عناوین: 29
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  • Leila Karimi, Seyed Mahmud Sadat Kiai *, Majid Elahi Pages 1-10
    In the present research, the properties of   clusters in a Paul ion trap have been investigated and confirmed through computational methods. Under different experimental conditions, we have confined obtained clusters for a specific time to identify their kinetic and spectroscopic properties. Also, the thermochemical results in various temperatures have been extracted for all  clusters in the present paper. The comparison of theory and experiment results confirms good agreement among them. Also, the structure of cluster and temperature conditions to formation of the cluster have been studied in the Paul trap and Calculate of the equilibrium constant of these clusters, in different temperatures was done. Based on the results, the formation of the cluster with n=2-3 is very easier than large cluster and they have symmetric structure.
    Keywords: Paul ion trap, Cluster of ions, Time of flight, equilibrium constant
  • Esmail Vessally *, Somayeh Mohammadi, Morteza Abdoli, Akram Hosseinian, Parisa Ojaghloo Pages 11-19
    Benzazole-2-ones (benzimidazolones, benzothiazolones, benzoxazolones) are important derivatives of benzazole compounds that exist widely in many biologically and pharmaceutically active molecules. Furthermore, benzazole-2-one derivatives also have many applications in agrochemical and material science. Herein, a novel, practical and green synthesis of titled compounds by the reaction of aniline derivatives with inexpensive and easily accessible sodium cyanate has been reported. Good to excellent yields of products have been obtained under catalyst- and ligand-free conditions in water as solvent. This procedure avoids the use of time-consuming and tedious column chromatography and the products were easily isolated by simple extraction followed by washing with dichloromethane.
    Keywords: benzazole-2-ones, Benzimidazolones, benzothiazolones, benzoxazolones, sodium cyanate, Green Chemistry, water, Synthesis
  • Noshin Seif, Asadollah Farhadi *, Rashid Badri, Ali Reza Kiasat Pages 21-33
    We report here an efficient and green method for fused Biginelli condensation reaction of aldehydes, cyclopentanone, and urea catalyzed by nano ZrO2-SO3H under solvent-free conditions. The prospect of the reusability of this catalyst has also been demonstrated without compromising on the yield of the product. On the whole, the protocol presented here is an excellent alternative to many of the previously reported procedures. So, Optimized molecular structures have been investigated by DFT/B3LYP method with 6-31G (d,p) basis set. Stability of some 4-aryl-7-benzylidene-1,3,4,5,6,7-hexahydro-4-phenyl-2H-cyclopenta[d]pyrimidin-2-one (2 a-j) derivatives and intramolecular interactions bond has been analyzed by using natural bond orbital (NBO) analysis.
    Keywords: Fused Biginelli condensation reaction, 4-aryl-7-benzylidene-1, 3, 4, 5, 6, 7-hexahydro-4-phenyl-2H-cyclopenta[d]pyrimidin-2-one, DFT, B3LYP, NBO
  • AliReza Aliabadi *, Hojat Harasami Neek, Yazdan Bahmani Pages 35-44

    Cancer is a lethal disorder that has caused a serious threat to human health and nowadays there is a crucial need for the development of novel anticancer agents. A new series of 1,3,4-thiadiazole-based compounds were synthesized and evaluated for anti-cancer properties in vitro. The synthesis of 5-(Trifluoromethyl)-1,3,4-thiadiazol-2-amine (3) was carried out via solvent-free conditions and consequently, benzamide (4a-4f) and benzothioamide (5a-5f) derivatives bearing halogen moieties  (Cl, F) were synthesized. MTT assay was applied for in vitro cytotoxicity assessment against three cancerous cell lines consist of PC3 (Prostate cancer), HT-29 (Colon cancer), and SKNMC (Neuroblastoma). All tested derivatives exhibited equal or more (IC50 = 3-7 µM) cytotoxic activity than doxorubicin (IC50 = 7 µM) as a reference drug against PC3 cell line. Chlorine containing benzamideas well as benzothioamide derivatives (IC50 = 14-36 µM) were also exerted a higher cytotoxic activity against SKNMC cell line compared to doxorubicin (IC50 = 40 µM).

    Keywords: Synthesis, 1, 3, 4-Thiadiazole, Anticancer, MTT assay
  • Muhammad Jamil, Nargis Sultana, Muhammad Sarfraz *, Muhammad Nawaz Tahir, Muhammad Tariq Pages 45-57
    A series of diamines derived transition metal complexes of naproxen with Zn(II), Cu(II), Ni(II), Co(II), Mn(II) have been synthesized and characterized by (FT)-IR, UV-Vis, NMR spectroscopy, magnetic susceptibility, and elemental analysis. Octahedral geometry has been proposed for all synthesized complexes based on magnetic susceptibility and electronic spectra. The crystal structures of Cu(II) complex with 1,2-diaminoethane (4b) is reported in this article. Structural studies provide the confirmation for the formation of Cu(H2O)2 (C2H8N2)2(np)2, which consists of two ionic naproxen moieties with different OMe orientation having intermolecular hydrogen bonding in solid-state. Jack bean Urease study of synthesized metal complexes was conducted and found that Cu and Ni complexes are more active having lower IC50 values against urease enzyme as compared to Zn, Co, and Mn complexes. Furthermore, urease inhibition studies showed that 1,2 diaminoethane and 1,3 diaminopropane derived transition metal complexes of naproxen (4a-e) and (5a-e), respectively have more inhibition efficacy as compared to simple metal naproxen complexes (3a-e). Amongst all, the synthesized complexes 4b and 4c have shown significant inhibition activities with IC50 values of 17.06 ± 0.05 and 18.07 ± 0.17 µM respectively, as compared to the standard drug thiourea.
    Keywords: Metal Complexes, Diamines, Crystal structure, Enzyme inhibition
  • Ahad Ghaemi *, Omid Vahidi, Salehi Mehrnoush Pages 59-69
    Hydrogenation of 2-Ethyl-3-Propylacrolein (EPA)in a three-phase fixed bed reactor is the most important part of 2-Ethyl-hexanol production in the Oxo process. In this research, hydrogenation of 2-Ethyl-3-Propylacrolein in a three-phase fixed bed reactor was modeling and simulated. The model equations including a set of partial differential equations were solved simultaneously using the method of lines and finite differences technique. The simulation with 80 elements of the hydrogenation reactor has 4.89 percent minimum deviation. Experimental data from laboratory scale reactor was used for evaluation of the hydrogenation reactor simulation results. The effect of operating conditions on 2-ethyl-hexanol yield was investigated in the temperature range of 130-160 oC, pressure range of 16-78 psi, hydrogen flow rate range of 150-220 mL/min, and 2-ethyl-hexenal flow rate in 0.04-0.11 mL/min. The results showed that increasing temperature, pressure, and hydrogen flow rate increases the EPA conversion whereas the variation of 2-ethyl-hexenal flow rate doesn't have any effect on the process yield.
    Keywords: Modeling, Simulation, Hydrogenation, 2-Ethyl-hexanol, Catalytic reactor
  • Masoumeh Ghalbi Ahangary *, Parviz Rashidi Ranjbar Pages 71-78
    Hierarchical SAPO-34 molecular sieve has been synthesized with n-propylamine as a mesoscale template and used to prepare La-Hierarchical SAPO-34 by impregnation by Lanthanum nitrate and has been used in Methanol-to-Propylene (MTP) conversion process. La-H-SAPO-34 demonstrated higher activity and selectivity for propylene (48.9%) compared to a conventional SAPO-34 catalyst (28.7%) in a fixed-bed reactor under atmospheric pressure at 450 oC and WHSV of 1.0 h-1. High selectivity and longer catalytic lifetime (7 hours) of methanol to propylene conversion have been attributed to the reduction in the acidic character of active sites and the increasing mesopore volume. The catalyst has been characterized by XRD, FE-SEM, BET, NH3-TPD, and TGA techniques and compared with SAPO-34.
    Keywords: Hierarchical SAPO-34, Methanol to propylene, Metal impregnated SAPO-34, Lanthanium oxide
  • Mehdi Mahmoudian, Keyvan Nosratzadegan, Mahmoud Ghasemi Kochameshki, Aref Shokri * Pages 79-94
    In this study, the modeling of polymerization of 1, 3-butadiene in the presence of hydrogen peroxide has been reported for the first time. For this purpose, the Method of double moments was applied. The modeling has been performed to investigate the effect of reaction condition on the properties of synthesized Polybutadiene, and the role of kinetic coefficients on the output of model i.e. sensitivity analysis. A comprehensive kinetic model was developed based on previous experimental studies. Then, the moment and population balance of the reactants were obtained. Modeling results were used to study the role of initiator concentration and the type of solvent in polymerization kinetics and final polymer properties. In addition, the sensitivity of modeling results in a transfer to the initiator, radical coupling, and finally transfer to polymer reactions was investigated. This study opens a way for the engineering of manufacturing the Hydroxyl-Terminated PolyButadiene (HTPB) process to obtain the desired products with optimized reaction conditions. Results show that initiator concentration and type of solvent are important in polymerization kinetics and properties of HTPBs. A higher amount of initiator increases radical concentration and consequently rates of bimolecular termination and at the lower level, rate of propagation, and polymer double bonds reactions.
    Keywords: Hydroxyl-terminated Polybutadiene (HTPB), 3-Butadiene, Radical polymerization, Molecular weight distribution (MWD), Initiator
  • Mehdi Mahmoudian, Keyvan Nosratzadegan, Jamshid Azarnia, Abbas Esfadeh, Mahmoud Ghasemi Kochameshki, Aref Shokri * Pages 95-110
    Living cationic ring-opening polymerization of cyclic ethers in the presence of diol was modeled using the method of moments. A widespread kinetic model was developed based on previous experimental studies. Then, the moment and population balance of reactants were obtained. Modeling results were employed to study the influence of initiator and water amounts (as the impurity) as well as feeding policy in polymerization kinetics and final properties of the polymer. In addition, the sensitivity of modeling results to initiation, backbiting, and finally propagation via activated monomer reactions were investigated. Results showed the population of chains is the function of their precursors. In a typical polymerization, chains with diol functionality are the majority. Therefore, most of the polymerized monomers are incorporated into those chains. This makes the chains with diol functionality the determining group in Molecular Weight Distribution (MWD). The kinetics of polymerization and properties of the reactor’s product are highly dependent on the ratio of the rate of propagation via the Activated Monomer (AM) mechanism to the rate of propagation via active chain end (ACE). An increase in this ratio decreases the probability of occurrence of backbiting reaction. Therefore, cyclic dimers are less formed and MWD narrows. On the other hand, decreasing this ratio results in less diol reacted with protonated monomers. Consequently, the rate of regeneration of the initiator and hence the rate of polymerization is decreased. These findings give complete facts about the ring-opening syntheses of polyethers and are valuable for evolving new grades as well as optimization current processes.
    Keywords: Ring-opening, kinetic model, Cyclic ethers, Molecular weight distribution (MWD), Method of moments
  • Ijaz Ahmed Khan, Hazart Hussain *, Tariq Yasin Pages 111-120
    This study deals with the synthesis and characterization of polyacrylonitrile (PAN)-grafted silica composite particles by emulsion graft polymerization using potassium persulphate as the initiator and Tween 80 as the surfactant for potential application in wastewater treatment. The commercially available silica particles (37-70 micron) were first functionalized with vinyltriethoxysilane that were subsequently employed for the grafting of PAN via emulsion polymerization. The effect of various experimental parameters, such as varying the amount of the monomer, initiator, and the emulsifier in the feed on the grafting (%) has been investigated in detail. The maximum grafting (296%) was achieved with 6% (w/v) monomer, 0.15% (w/v) initiator, and 1% (w/v) emulsifier concentration. The nitrile groups of the PAN-grafted silica composite particles were converted into amidoxime by treating with hydroxylamine. The synthesized products in all the preparation steps were carefully characterized by various analytical tools, i.e., Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD). In FTIR spectrum of the silica-grafted PAN, the appearance of the characteristic peak at 2245 cm-1 that corresponds to CN stretching confirms the successful grafting of PAN onto the modified silica particles; while the transformation of nitrile into amidoxime functionality was verified by the appearance of peaks at 1642 cm-1 and 920 cm-1. Further verification of the grafting of PAN and amidoxime formation also comes from the SEM micrographs and the XRD profiles. Finally, the obtained amidoxime-grafted silica composite particles were evaluated as an adsorbent for Cu+2 ions from the simulated wastewater for potential application in wastewater treatment. The maximum adsorption capacity of 130 mg/g was achieved at pH 5 in 2 hrs.
    Keywords: Composite, Grafting, silica, Emulsion polymerization, Amidoxime, Wastewater treatment
  • Samira Khodabakhsh, Ebrahim Alaiee, Lobat Taghavi *, Leila Samiee Pages 121-130
    Since phenol is toxic and yet its biologic reduction and removal is so difficult, strict limits are applied for the discharge of phenol-containing substances in the environment. Discharge of phenol-containing industries, sewages into natural waters is a serious threat to human health. In this study, the main objective is to consider the possibility of removing phenol with high initial concentration using a Heterogeneous Photocatalytic process. First, the absorbent SBA-15 and Graphene oxide(GO), which are the most efficient absorbents among others for phenol removal, and then, nanocomposites Titanium dioxide(TiO2)/SBA-15 and TiO2/GO were synthesized. Then, the structural and physical properties of nanocomposites were identified through X-Ray Diffraction (XRD), Brunauer–Emmett–Teller (BET), Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM) analysis. Considering the results of the Response Surface Method (RSM) for phenol removal in the initial study, nanocomposites TiO2 / SBA-15 and TiO2 / GO were used to remove the same amount of phenol from aqueous solutions.
    Keywords: Phenol, Heterogeneous Photocatalytic process, Tio2, SBA-15 Nanocomposite, TiO2, GO Nanocomposite, Response surface methodology
  • Maryam Daraee, Majid Baniadam *, Ali Morad Rashidi, Morteza Maghrebi Pages 131-144
    In this study, nitrogen-doped MWCNT-TiO2 nanocatalyst (N-CNT-TiO2) with 1, 3, and 5 wt. % nitrogen has been synthesized and its catalytic activity in the oxidation of H2S to sulfur has been studied at a temperature of 200°C and O2/H2S mole ratio of 0.5 and compared with those of neat TiO2 and TiO2-CNT hybrid. Their structure, morphology, and chemical properties have been determined by N2 adsorption-desorption isotherms, XRD, SEM, TEM, UV, and FT-IR. N-CNT-TiO2 exhibited improved performance compared with TiO2-CNT due to the presence of nitrogen groups. In addition, the nanocatalyst was comparable (up to 5%) with TiO2 because of the presence of a lower bandgap and synergistic effects. Furthermore, 5%N-CNT-TiO2 has shown the highest catalytic activity among N-CNT-TiO2 nanocatalysts due to its higher surface area and pore volume.
    Keywords: N-CNT-TiO2, nanocatalyst, Nitrogen group, Catalytic activity
  • Maryam Azarian, Amir Amani, MohammadAli Faramarzi, Akram Eidi, Adeleh Divsalar * Pages 145-155

    Noscapine is an antispasmodic alkaloid used as antitussive and anti-cough obtained from plants in the Papaveraceae family which this benzylisoquinoline alkaloid and its synthetic subsidiaries (called noscapinoids) are being assessed for their anticancer potential.  The present research aimed to investigate the induction of DNA destruction and viability of HepG2 tumor spheroid culture influenced by noscapine and nanosuspension of noscapine. Culture of HepG2 cells as spheroids was treated with different concentrations of noscapine for 24 h on Day 11. Afterward, viability assay and alkaline comet assay methods were applied to examine the viability and induced DNA destruction, respectively. Based on the results, no significant impact was observed from Tween 40 on the viability and DNA damage levels in comparison with the control (p > 0.05). Moreover, increasing noscapine concentration resulted in a dose-dependent reduction in viability of hepatic cancer cells and elevation of DNA damages, showing a correlation between rises of DNA damages and viability decline.

    Keywords: Genotoxicity, Noscapine, Nanosuspension, Microfluidic Reactors, HepG2
  • Noushin Raeisi Kheirabadi, Noosheen Salman Tabrizi, Parvaneh Sangpour * Pages 157-168
    In this study, carbon aerogel was prepared from sodium alginate via the sol-gel technique. The morphological study clearly revealed that the synthesized aerogel possessed a highly porous structure with a specific surface area of 470 m2/g. The applicability of the aerogel as an adsorbent was examined in methylene blue removal. Adsorption isotherms, kinetics, and thermodynamic studies of Removal of MB from aqueous solutions were conducted in a batch system. The effect of pH and adsorbent dosage on the adsorption of MB was investigated. The equilibrium data were best fitted to the Langmuir model with a maximum adsorption capacity of 70.42 mg/g. The adsorption kinetics of MB followed the pseudo-first-order models. Thermodynamic analysis of the results indicated that adsorption is a physical process and is in agreement with data obtained from the Dubinin−Radushkevich isotherm model. The removal of the MB process was spontaneous and endothermic.
    Keywords: Carbonaceous aerogel, Methylene blue, adsorption model, Kinetics
  • Manel Araissi, Elimame Elaloui *, Younes Moussaoui Pages 169-179
    The article aims to study the removal of heavy metal ions Cd2+, Co2+, and Ni2+ from an aqueous solution using faujasite NaY. The adsorption studies were carried out in the single and binary component system. Sorption experiments were performed in batch at pH (5–6), adsorbent dosage (0.15 g), and initial concentration (0.1–10 mmol/L). The single-ion equilibrium adsorption data were fitted to three isotherm models: Langmuir, Freundlich, and Dubinin-Radushkevich. Results showed that the Langmuir isotherm fits sorption data better than the Freundlich equation. The maximum adsorption capacities (Qmax) were 0.81, 0.85 and 0.92 mmol/g for Cd2+, Ni2+ and Co2+ ions, respectively. Besides, the study of the competitive sorption of ions in a binary system showed that faujasite NaY preferentially adsorbs cations in the following order: Co2+>Ni2+>Cd2+. The obtained RL (separation factor or Langmuir parameter) values were in the range of 0–1 indicating that Cd2+, Co2+, and Ni2+ sorption were favorable. The obtained mean free energy value for adsorption of Co2+ and Ni2+‏were in the range of 8–16 kJ/mol, indicating that ions were uptaken through an ion exchange process.
    Keywords: Faujasite NaY, Competitive adsorption, heavy metals, Isotherm modeling
  • Burcu Kabak, Diğdem Trak, Erdal Kenduzler, Fatma Tomul, Yasin Arslan * Pages 181-189
    A selective solid-phase extraction method has been developed for the preconcentration and separation of trace amounts of Co(II). The method was based on the adsorption of Co(II) ions on the Amberlite CG-120 resin. The adsorbed Co(II) ions on the resin were eluted by 4 mol/L HCI and then they were determined by Flame Atomic Absorption Spectrometry (FAAS). Various experimental conditions, such as pH, type and concentration of eluent, the flow rate of sample and eluent solution, amount of resin, and sample volume were investigated to obtain better sensitivity and effective separation of trace levels of the Co(II) ions. Moreover, the interference effects of some ions on the recovery of Co(II) were also investigated. The developed method was applied for the determination of Co(II) ions in drinking and wastewater samples. The enhancement factor (EF) and limit of detection (LOD) values were found to be 25-fold and 9.32 µg/L, respectively. The accuracy of the method was tested by the certified reference material of TMDA-70.2 Lake Ontario Water and there was a good agreement between found and certified values at a 95% confidence level.
    Keywords: Cobalt, Amberlite CG-120 resin, Solid-phase extraction, Water samples, FAAS
  • Haythem Barrak *, Abdelkader Kriaa, Mohamed Triki, Adel MNif, Ahmed Hichem Hamzaoui Pages 191-201

    This paper explores the adsorptive properties of CaF2 nanoparticles for the removal of Pb(II) and Zn(II) from aqueous solutions and their selective recovery. CaF2 nanoparticles were synthesized by a facile one-step reaction and characterized by N2 physisorption at 77 K, XRD, and TEM. The adsorption of Zn(II) and Pb(II) fits well with Elovich and Langmuir isotherm models, respectively. Kinetic data are well described by the pseudo-second-order model. Our results show that Zn(II) and Pb(II) could be totally and selectively desorbed with HCl solution (0.01 M). The results of the competitive adsorption and desorption of Pb(II) and Zn(II) show that Zn(II) is desorbed before Pb(II) leading to a good separation. The desorption yield reaches 89% for Zn(II) and 95% for Pb(II), which opens the route to regenerate the adsorbent for other cycles.

    Keywords: heavy metals, Adsorption, Desorption, competition, CaF2
  • Balasubramani Kavitha *, D .Sarala Thambavani Pages 203-223

    Removal of Cr(VI), Ni(II), and Cu(II) from aqueous solution by Riverbed Sand containing Quartz as major clay minerals as a non-toxic and economically viable treatment was investigated. The structure, morphology, surface area, and elemental composition were confirmed using XRD, SEM, EDAX, FT-IR, and BET techniques. The N2 adsorption-desorption isotherm reveals their mesoporous structure and large BET surface area (122.75 m²/g). The effect of the initial metal concentration, pH, adsorption dosage, contact time, and temperature were examined in batch experiments to understand adsorption isotherms, kinetics, and thermodynamics. Results suggest that the equilibrium adsorption was described by the Langmuir model. Adsorption kinetics was described well by the pseudo-second-order model and were followed by an intraparticle diffusion mechanism. The thermodynamics studies reveal that the adsorption was spontaneous and exothermic. An Artificial Neural Network (ANN) model was used to optimize the removal efficiency of Cr(VI), Ni(II), and Cu(II) on QKCI. The model was developed using a three-layer feed-forward backpropagation algorithm with 15, 18, and 20 hidden neurons for Cr(VI), Ni(II), and Cu(II) ions. Comparison between the model results and experimental data gives a high degree of correlation (R2= 0.9863 for Cr(VI), 0.9591 for Cu(II)) and 0.9469 for Ni(II) indicating that the model is able to predict the sorption efficiency with reasonable accuracy.

    Keywords: Adsorption, Isotherm, Kinetics, Thermodynamics, Artificial neural network models
  • Mohamed A. Gado *, Bahig M. Atia, Mohamed S. Hagag Pages 225-237
    Magnetic Graphene Oxide(MGO) impregnated Di(2-Ethyl Hexyl)Phosphoric Acid (D2EHPA) (DMGO) was prepared by multi-impregnation. The structures of GO and DMGO were characterized by FT-IR, TGA, EDX, SEM, and XRD. The adsorption capacity for U(VI) from aqueous solution is 154.4 mg/g  at pH 5. The essential factors that affected U(VI) adsorption such as initial pH, contact time, and temperature were investigated. The adsorption is highly dependent on the solution pH. In addition, the adsorption isotherm and thermodynamics were investigated. The adsorptions of U(VI) from aqueous solution on DMGO was fitted to the Langmuir adsorption isotherms. The adsorption of U(VI) on DMGO is remarkably improved byGO impregnated with D2EHPA. Thermodynamic parameters further show that the sorption is an endothermic and spontaneous process. DMGO is a powerful promising sorbent for theefficient removal of U(VI) from aqueous solutions.
    Keywords: Uranium. Adsorption, D2EHPA, Graphene oxide, Impregnation
  • Qazi Nasir *, Humbul Suleman, Manivannan Elumalai Pages 239-254
    Amine and membrane based process are commonly used to treat acid gases such as carbon dioxide and hydrogen sulfide. Carbon dioxide adversely affect the environment therefore, its utilization and storage are critical. In this work, a simplistic approach of single stage membrane unit combine with amine absorption processes with different commercial amines were investigated. Increase in CO2 concentration in the feed gas, results in substantial increase in the thermal energy consumption of the stripper reboiler, where using hybrid amine-membrane setup can effectively reduce energy consumed in reboiler. Both amine absorption process and membrane process are simulated using Aspen HYSYS V10. Since, membrane is not available in Aspen HYSYS V10 unit operation package, it is programmed and added as custom user operation. Moreover, a new acid/ amine based fluid package builds in combination of Peng-Robinson equation of state for vapor phase and electrolyte non-random two liquid based activity model for liquid phase were used in this study. Furthermore, energy consumption in CO2 capture using different alkanolamine such as N-methyldiethanolamine (MDEA), monethanolamine (MEA), deithanolamine (DEA), piperazine (PZ), triethanolamine (TEA) are also studied. As membrane unit help in CO2 reduction in feed to amine absorption process in hybrid amine-membrane setup. This significantly reduces the energy requirement as compared to the conventional standalone alkanolamine process. In comparison with various amines used in amine absorption process, MEA offers the lowest total energy consumed, whereas, MDEA considered to be the highest in terms of energy consumption.
    Keywords: Amine absorption process, Membrane process, Hybrid Process, ASPEN HYSYS, MEA, DEA
  • Mahsa Saeidi, Ahad Ghaemi *, Kambiz Tahvildari Pages 255-267
    In this research, KOH has been evaluated as a solid adsorbent for carbon dioxide (CO2) capture. The effect of pressure, temperature, and KOH loading on CO2 adsorption in a fixed-bed reactor were investigated. Response Surface Methodology (RSM) based on the central composite design (CCD) was used to evaluate the effects of operating parameters on adsorption capacity in order to achieve the optimum conditions. The experimental values of the responses were in decent agreement with the predicted result of regression models. Techniques such as Fourier Transform InfraRed (FT-IR) spectroscopy and X-ray diffraction (XRD) were used to study the consider KOH sorbent. The results show that CO2 adsorption is improved with the loading of 0.5 g of KOH. The maximum CO2 adsorption capacity was acquired for KOH at temperature 45°C and pressure 6 bars. The Freundlich model was found to be the best for fitting the adsorption of CO2 owing to the closeness of the R2 to unity. Furthermore, the kinetic study specified that the first-order model is well-fitted with the experimental data. Overall, the very high surface area of KOH adsorbent makes this adsorbent new promising material for CO2 capture.
    Keywords: CO2 Adsorption, KOH sorbents, Response surface methodology (RSM), Isotherm, Kinetics
  • Yasser Ghalmi, Abdelfetteh Sayah *, Farid Habelhames, Imad Henguesmia, Ahmed Bahloul, Belkacem Nessark Pages 269-274
    Graphene (Gr) synthesized by electrochemical exfoliation method has been used to prepare the composite material (PbO2-Gr) including different amounts of graphene (1 and 5%). Taking into account the advantages of the high conductivity of Gr and the capacitance of PbO2, as a reference, the PbO2-Gr composite material served for the application in lead-acid batteries as a positive electrode. On one hand, the morphology and structure of the whole pure graphene, PbO2, and PbO2-Gr were characterized by different technics XRD, TEM, and electrical conductivity. The electrochemical performance was evaluated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry, and galvanostatic discharge tests. The discharge capacity of the PbO2 material experienced is around 40mAh which witnessed an increase of 53mAh regarding the composite material PbO2-Gr1%.
    Keywords: Graphene, PbO2, composite material, discharge capacity, lead-acid battery
  • Nagashanmugam Krishna Chettiar *, Anit Chanda, Subrata Panti, Rabindrakumar Patra Pages 275-284
    In the backdrop of war and amid sanctions on Syria, a mini blast furnace has been successfully recommissioned in Hassia, Syria, and the hot metal produced is used for the production of 130 mm2 mild steel billets, providing import substitution as presently the billets are being imported from countries such as Russia, Ukraine, etc. Emmar Steel (ES) is an integrated steel plant having a production capacity of about   0.5 million tons of steel per annum.  ES operates a mini blast furnace (MBF) with a designed capacity of   500 TPD (tons per day) to produce hot metal. ES is the only steel plant, which houses a blast furnace and the first of its kind in the whole of Syria, the Gulf region, and in the countries surrounding Syria (excluding Turkey). In the past two decades, almost all blast furnaces across the globe use a charge burden consisting of various permutations and combinations of iron ore, sinter/pellets of iron-bearing materials as sources of iron depending on their availability, ease of operation, and economies of scale. But, sometimes due to the non-availability of iron ore fines, sintering, and pelletizing facilities, it becomes necessary to manage the charging burden only with iron ore as the sole source of iron. The present paper describes the efforts taken to achieve a low coke rate of 568 kgs/ton of hot metal (THM) during the recommissioning period of about 4 months (May to August 2018), wherein it produced about 56800 tons of hot metal from about 86100 tons of calibrated iron ore with peak production of 650 TPD against the designed capacity of 500 TPD in the mini blast furnace of ES located at Hassia, Syria.
    Keywords: Emmar Steel, Mini Blast Furnace, Iron making, Metallurgical coke, Coke rate, CRI & CSR, M40 & M10, Burden charge
  • Reza Gholipour Peyvandi *, Seyedeh Zahra Islami Rad Pages 285-291
    The ability to precisely detect the interface of the different phases in a vessel plays an important role in chemical plants, oil, and petroleum industry. The purpose of this research is to apply the gamma-ray attenuation technique (single point source and single detector) together with MultiLayer Perceptron (MLP) neural network to detect the interface present in water-gasoil two-phase flows in pipelines and vessels, for the first time. The experimental setup is comprised of a plastic rod scintillator (BC400) coupled with two PMT tubes at two sides as a position-sensitive detector, a point gamma-ray source (137Cs), and a vessel between the source and detector. The detection system provides the required data for training and testing the network. Using this proposed method, the interface locations were determined in two-phase with mean relative error percentages less than 0.34% and 0.27% for levels of water and gasoil, respectively. The mean absolute error values were measured less than 1.16 and 1. Also, the correlation coefficients were calculated 0.999 and 1. These results presented the accuracy of the proposed method in order to determine the interface position. The used set-up is simpler than other proposed techniques and cost, radiation safety, shielding requirements, and risk production are minimized.
    Keywords: Interface level position, Plastic rod scintillator, Artificial Neural Network, Single point source - single detector
  • Fereshte Khanramaki, Rezvan Torkaman, AmirSaeed Shirani *, Jaber Safdari Pages 293-305

    To carry out this investigation, drop behavior in a horizontal pulsed sieve-plated column was measured under with and without reactive extraction situations. Central composite design, a subcategory of response surface methodology, was utilized to survey the influence of the operational parameters on the drop behavior. The effect of the reactive extraction situation was also observed on droplet behavior. According to the experimental results, the effect of pulse intensity on the droplet behavior was greater than the phase flow rates. For the prediction of the Sauter mean drop diameter in a reactive extraction situation, a new correlation was determined. The results obtained via the proposed correlation were closely matched with the experimental results (AARE is about 6.64%). Also, to determine a predictive correlation for drop size distribution, log-normal, and normal probability density function were examined. The constant parameters at these probability density functions are specified by the obtained results as well as the mathematical approach.

    Keywords: Sauter Mean Drop Diameter, probability density function, Horizontal Pulsed Column, Extraction efficiency, Central composite design
  • Ali Reza Saatchi, Hadi Seddiqi, Ghassem Amoabediny *, Marco N. Helder, Behrouz Zandieh Doulabi, Jenneke Klein Nulend Pages 307-320

    Bone tissue engineering strategies use fluid flow dynamics inside 3D-scaffolds in perfusion, bioreactors mechanically stimulate cells in these scaffolds. Fluid flow dynamics depends on the bioreactor’s inlet flow rate and 3D-scaffold architecture. We aimed to employ a computational evaluation to assess fluid dynamics in 3D-printed scaffolds with different angular orientations between strands in each layer inside a perfusion bioreactor at different inlet flow rates. 3D-printed cubic scaffolds (0.6×0.6×0.6 cm; total volume 216×10-3 cm3) containing strands (diameter 100 µm) with regular internal structure and different angular orientation (30°, 45°, 60°, and 90° between strands in each layer) were used for modeling. The finite element method showed that the perfusion bioreactor’s inlet flow rate (0.02, 0.1, 0.5 mL/min) was linearly related to average fluid velocity, average fluid shear stress, and average wall shear stress inside 3D-printed scaffolds with different angular orientation (30°, 45°, 60°, 90°) between strands in each layer. At all inlet flow rates, strands at 30° angular orientation increased average fluid velocity (1.2-1.5-fold), average fluid shear stress (6-10-fold), and average wall shear stress (1.4-2-fold) compared to strands at 45°, 60°, and 90° angular orientation providing similar results. In conclusion, significant local changes in fluid dynamics inside 3D-printed scaffolds result from varying the degree of angular orientation between strands in each layer, and the perfusion bioreactor’s inlet flow rate. By decreasing the angular orientation between strands in each layer and increasing the inlet flow rate of a perfusion bioreactor, the magnitude and distribution of fluid velocity, fluid shear stress, and wall shear stress inside the scaffold increased. The average fluid velocity, average fluid shear stress, and average wall shear stress inside the scaffold within the bioreactor increased linearly with the inlet flow rate. This might have important implications for bone tissue engineering strategies using cells, scaffolds, and bioreactors.

    Keywords: Bone tissue engineering, Fluid flow dynamics, perfusion bioreactor, 3D-printed scaffold, Finite element modeling, strand orientation
  • Mostafa Varmazyar, Mohammadreza Habibi *, Jalil Jafari, Aghil Barati Pages 321-332
    Gas Engine Heat Pump (GEHP) is found as an effective machine among energy conversion systems. However, further improvement of GEHP performance is still indispensable. In the current study, to recycle efficiently the flue gases waste heat of GEHP unit, it is suggested to utilize a condensing heat exchanger. To assess the performance of the proposed GEHP, an equipped test room was designed. The nominal capacity of the current GEHP is about 80 kW for heating and 71 kW for cooling. The experimental investigation was implemented for two common strategies, i.e. heating and cooling modes. The effect of outlet dry bulb temperature of 0 °C, 5 °C, 10 °C and 15 °C for heating, and 25 °C, 30 °C, 35 °C and 40 °C for cooling as well as water outlet temperature of 40 °C, 45 °C and 50 °C for heating and 8.5 °C, 11 °C, 14 °C for cooling on the performance of the GEHP is investigated. The 95% confidence interval has been considered in statistical analysis. In heating mode, results show that the efficiency of the condensing heat exchanger increases during the reduction of water out temperature and it leads to a Coefficient of Performance (COP) enhancement. Additionally, observation indicates that the decrement of the ambient air temperature from 5 to 0 ° C leads to the severe enhancement of fuel consumption of the gas engine. The performance indicators are re-evaluated using the non-condensing heat exchanger. It is concluded that the COP of GEHP with the condensing heat exchanger decreases by the steeper slope versus the reduction of the ambient dry bulb temperature compared to the non-condensing heat exchanger.
    Keywords: Gas engine heat pump, condensing heat exchanger, heating, cooling mode, performance map
  • Ghassem Zargar, MohammadAli Takassi, Siamak Moradi, AliReza Rostami *, Babak Jabari Pages 333-341

    Wettability alteration is an important mechanism when applying surfactants during enhanced oil recovery (EOR). Moreover, in carbonate reservoirs, the rock has more tendencies to be oil-wet than those of sandstone reservoirs. This mainly arises from the interaction amongst the carbonate surface chemistry exposed to the asphaltenic/aromatic components of crude oil. Therefore, it is of great significance to develop surfactants with high efficiency in wettability alteration of carbonate rocks. In this work, a cationic surfactant n-dodecyl trimethylammonium bromide (DTEAB), was prepared and applied in a wettability alteration experiment for the first time. Then, the critical micelle concentration and wettability properties were studied by means of electrical conductivity and sessile drop techniques, respectively. Consequently, it was observed that this surfactant can alter the wettability of Bangestan rock pellets from oil-wet to water-wet state, and the results are better than that of wettability alteration observed for Khark rock pellets. Based on this mechanism, nearby 22% Original Oil in Place (OOIP) was obtained by tertiary surfactant flood during core displacement in excess of ultimate recovery factor of secondary water injection. As a consequence, the suggested cationic surfactant in this study can be a good agent for increasing the oil recovery factors in the petroleum industry.

    Keywords: n-dodecyltriethylammonium bromide (DTEAB), Cationic surfactant, Critical micelle concentration (CMC), wettability alteration, Core displacement
  • Mohsen Yavari, Sirous Ebrahimi *, Valeh Aghazadeh, Mohammad Ghashghaee Pages 343-352
    A one-stage process for the bioleaching of copper from chalcopyrite has a low leaching rate compared to the conventional smelting, pressure oxidation, and roasting routes, thus reducing the economic viability of the process. It is, therefore, crucial to optimize the process and the associated rate-influencing factors to make it competitive with the traditional, proven technologies. A strategy to intensify the extraction process is the decoupling of the chemical and biological stages, which expands the attainable region for the optimization of the variables. In the present research, the decoupled optimization of the chemical stage in the copper bioleaching of a chalcopyrite ore from the Iranian Sungun mine at East Azerbaijan was investigated. The factors affecting the rate of oxidation of chalcopyrite were determined and optimized with a (realistic) priori prepared bio-related medium. The optimized variables included the reaction temperature of 70 °C, the ore particle size of 0.65 μm, pH of 1.8 in the leaching solution, ferric ion concentration of 0.1 of the stoichiometric value (0.0022 mol per gram of chalcopyrite), and redox potential ~406 mV. Overall, the effect of redox potential on the extraction rate was the most pronounced such that the leaching rate was increased by about three times in the potential range of 401.0–405.8 mV relative to other ranges.
    Keywords: Process optimization, Bioleaching, ferrous sulfate, chalcopyrite, copper sulfide