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Iranian Journal of Chemistry and Chemical Engineering - Volume:36 Issue: 5, Sep-Oct 2017

Iranian Journal of Chemistry and Chemical Engineering
Volume:36 Issue: 5, Sep-Oct 2017

  • تاریخ انتشار: 1396/10/03
  • تعداد عناوین: 17
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  • Ali Reza Razeghizadeh *, Lila Zalaghi, Iraj Kazeminezhad, Vahdat Rafee Pages 1-8
    SnO2 nanoparticles with different percentage of Al (5%, 15%, and25%) were synthesized by sol-gel method. The structure and nature of nanoparticles are determined by of X-ray diffraction analysis. Also, morphology of the samples is evaluated by SEM. Moreover, the optical properties of the samples are investigated with UV-Visible and FT-IR. The XRD patterns are indicated that all samples and incorporation aluminum ions into the SnO2 lattice have tetragonal rutile structure. The crystalline size of nanoparticles is decreased with increasing the Al percentage. The SEM results confirmed that the size of nanoparticles decreases with increasing the Al percentage. Also, FT-IR and UV-Visible results showed that the optical band gap of nanoparticles increases with the increasing the Al percentage. Finally, we have used the EDX analysis to study the chemical composition of the products. Pure tin and oxygen have been observed. The doped samples showed the existence of Al atoms in the samples of the crystal structure of SnO2.
    Keywords: Nanoparticles, SnO2, Sol, gel, Al, doped, Optical Properties
  • Maryam Robati, Dadkhoda Ghazanfari, Mohammad Reza Islami *, Kazem Saidi Pages 9-16
    A series of novel 1, 8-dioxo-octahydroxanthene derivatives containing 4-thiazolidinone framework (4a-f) were synthesized through a four-step reaction starting from the reduction of nitro derivatives of 1, 8-dioxo-octahydroxanthenes. The resulting aminoxanthenes converted to thiourea derivatives via their reaction with methyl isothiocyanate. The final products were synthesized through the reaction of thiourea derivatives with dialkylacetylene dicarboxylates. All of the steps were carried out under easy and mild reaction conditions in the absence of expensive catalysts or esoteric starting materials. The structures of compounds 3a-c and the final products were characterized according to their physical constants, spectral data such as NMR, IR spectra and also elemental analysis.
    Keywords: 1, 8, dioxo, octahydroxanthene, 4, thiazolidinone, dialkyl acetylene dicarboxylate, dimedone, 1, 3, cyclohexanedione
  • Hossein Anaraki-Ardakani *, Parisa Nkomanesh Pages 17-22
    A simple and efficient synthesis of some polyfunctionalized pyrrole derivatives by a triphenylphosphine-promoted condensation reaction between dialkyl acetylenedicarboxylates, arylglyoxals, and ammonium acetate is described. This present method carries several advantages, such as good yields, a simple procedure, non-hazardous reaction conditions and starting from easily accessible substrates
    Keywords: Dialkyl acetylenedicarboxylates, Triphenylphosphine, Ammonium acetate, Intramolecular Wittig reaction, Arylglyoxals
  • Yaser Jafari, Sayed Mehdi Ghoreishi *, Mehdi Shabani-Nooshabadi Pages 23-32
    The synthesis of polyaniline doped with dodecylbenzene sulphonic acid (Pani-DBSA) coatings on 310 stainless steel (310 SS) surfaces has been investigated by using the galvanostatic method. The synthesized coatings were characterized by Fourier Transform Infrared Spectroscopy (FT-IR), UV-Visible absorption spectrometry and Scanning Electron Microscopy (SEM).The anticorrosion performances of Pani-DBSA coatings were investigated in 5% NaCl solution by the potentiodynamic polarization technique and Electrochemical Impedance Spectroscopy (EIS). The corrosion rate of Pani-DBSA coated 310 SS was found ∼30 times lower than bare 310 SSand potential corrosion increased from -0.84 V versus Ag/AgCl for uncoated 310 SS to -0.71 V versus Ag/AgCl for Pani-DBSA coated 310 SS electrodes. Electrochemical measurements indicate that Pani-DBSA coated have good inhibiting properties with a mean efficiency of ~96% at 5 mA cm-2 current density applied to 310 SS corrosion in chloride media. The results of this study clearly ascertain that the Pani-DBSA has an outstanding potential to protect 310 SS against corrosion in a chloride environment.
    Keywords: Electrosynthesis, 310 Stainless Steel, Corrosion, EIS, dodecylbenzene sulphonic acid
  • Sepideh Hamedi, Seyed Abbas Shojaosadati, Soheila Shokrollahzadeh *, Sameereh Hashemi-Najaf Abadi Pages 33-42
    The focus of this study was to evaluate the effects of some parameters influencing the size and size distribution of the silver nanoparticles (AgNPs) produced by culture supernatant of Fusarium oxysporum. Results revealed that in the reaction solution containing equal volume of silver nitrate and culture supernatant; pH, temperature, and light source can control the AgNP’s characteristics. The particle size decreased with an increase in pH. The average size of AgNPs, formed in reaction solutions, decreased as temperature increased from 40 °C to 121 °C. The smallest AgNPs with the highest polydispersity (average size of 14nm and PDI of 0.37) were obtained in reaction solution incubated at 121 °C. Also, the use of UV radiation in reaction solution resulted in the production of the very small AgNPs with the narrowest size distribution (average size of 9.7nm and PDI of 0.2). X-ray diffraction analysis verified the crystalline nature of synthesized AgNPs. Also, transmission electron microscopy analysis confirmed the production of spherical shape nanoparticles.
    Keywords: Silver nanoparticles (AgNPs), Controlled Biosynthesis, Fusarium oxysporum, culture supernatant
  • Hassan Mansouri Torshizi *, Sareh Zareian-Jahromi, Maram Saeidifar, Ali Ghasemi, Hamed Ghaemi, Ali Heydari Pages 43-54
    Seven reported xanthate ligands and their new Fe(II) complexes of formulaNa[Fe(R-OCSS)3], where R is ethyl-, propyl-, butyl-, pentyl-, Hexyl-, heptyl- and octyl-xanthate have been synthesized. They have been characterized using elemental analysis, molar conductance, FT-IR, UV-Vis and 1H NMR spectroscopic techniques and melting-, decomposition-points for ligands and complexes respectively. All the ligands and their Fe(II) complexes have been evaluated for their antimicrobial activity against four gram-positive bacteria, four gram-negative bacteria and three fungi by agar disc diffusion technique. The MIC values of the compounds exhibited significant antifungal activity but showed lower antibacterial activity. The iron(II) complexes are found to possess higher antimicrobial activity than their counterpart ligands thus improving its antimicrobial efficacy. Hydrocarbon chain length of the ligands coordinated to Fe(II) centers seemed to be important for their antifungal as well as antibacterial activities.
    Keywords: Xanthate, Fe(II) complex, Antifungal activity, Antibacterial activity
  • Hadi Abusaidi, Hamid Reza Ghaieni *, Mostafa Ghorbani Pages 55-63
    The present study describes the effect of NCO/OH and triol/diol ratios on the mechanical properties of Nitro functionalized Hydroxyl-terminated polybutadiene (Nitro-HTPB) elastomers. The progress of the cure reaction of Nitro-HTPB and toluene diisocyanate (TDI) is evaluated by following up the variations in the IR absorption bands of the NCO stretching and the CO Stretching. Experiments are carried out at NCO/OH ratios (R values) ranging from 0.8 to 1.2 and triol/diol ratios in the range of 0.05-0.7. Also as the R-value increases, the tensile strength increases, and elongation decreases. The rubbery character of elastomers is improved followed by increased rigidity with an increase in triol/diol value of 0.05. In general, desirable mechanical properties were achieved for the polyurethane elastomers of Nitro-HTPB as a novel energetic binder.
    Keywords: Mechanical properties, Elastomer, Nitro, HTPB, Polyurethane, TDI
  • Reza Shahinfar, Saeid Khanzadi *, Mohammad Hashami, Mohammad Azizzadeh, Aram Bostan Pages 65-75
    Ziziphora clinopodioides is from the genus of Ziziphora and family of Lamiaceae,which grows in Iran and Turkey. This study was conducted to preserve the chemical and microbial quality of trout fish burger during storage using Ziziphora clinopodioides essential oil (ZEO) individually and in combination with nisin. Firstly, the chemical composition of ZEO was determined using GC-MS analysis. Different treatments of trout fish burger were formulated using ZEO and nisin as natural preservatives, stored in refrigerator for 20 days and were analyzed for chemical (pH and Total Volatiles Base-Nitrogen (TVB-N)) and microbial (total viable count, psychotropic counts, Enterobacteriaceae count and Pseudomonas spp count) characteristics.at 5-day intervals.The Results indicated a yield of 1% (w/w) for ZEO isolation and Pulegone (40.09%), Menthone (13.76%) and Isomenthone (12.31%) were identified as the major components of phytochemicals of ZEO. According to the obtained results combination of ZEO and nisin had the strongest effect on chemical and microbial quality of fish burger; however, their individual use had significant effects on preserving the chemical and microbial quality of fish burger as well. based on results of this study, formulation of ZEO and Nisin in fish burger especially in combinations can prolong its shelf life and control chemical and microbial changes during storage at 4˚ C.
    Keywords: Chemical composition, Chemical quality, Fish burger, Total volatile base nitrogen, Ziziphora clinopodioides
  • Reza Shahinfar, Saeid Khanzadi *, Mohammad Hashami, Mohammad Azizzadeh, Aram Bostan Pages 77-88
    The present study aimed to evaluate the effect of free and microencapsulated Ziziphora clinopodioides Essential Oil (ZEO) and Nisin individually and in combinationon sensory characteristic and shelf life of fish burger during 20 days of storage at 4±1˚C. Fish burgers were prepared and treated with free and microencapsulated form of ZEO and Nisin in 15 treatments and evaluated by 20 stable semi-trained people using a 9-point hedonic screen method on days 0, 5, 10, 15, 20. The chemical composition of fish burgers was also analyzed at the first day of storage. Results indicated that both microencapsulation and combinational use of ZEO and Nisin improved sensorial scores of treated samples during 20-day storage at 4±1˚C (P
    Keywords: Hedonic scale, Sensory analysis, Fish burger, Encapsulation
  • Sahar Mohajeri *, Maziar Noei, Nazanin Molaei Pages 89-98
    Electrical sensitivity of a Boron Nitride Nano Tube (BNNT) was examined toward hydroquinone (C6H4(OH)2), cyanogens (C2N2), methylacetylene (C3H4), ethylacetylene (C4H6), aniline (C6H5NH2), ethanol (C2H5OH), pyrrole (C4H5N), molecules by using Density Functional Theory (DFT) calculations at the B3LYP/6-31G(d) level of theory. In considering the dsorption energy (Ead) of those molecules on the BNNT are sequenced: C6H5NH2(Ead= -47.55kcal/mol)> C4H5N (Ead=-26.66kcal/mol) >C2H5OH(Ead= -25.91kcal/mol)> (CN)2(Ead=-20.70kcal/mol)> C6H4(OH)2(Ead= -20.21kcal/mol) >C3H4(Ead=-12.73kcal/mol)> C4H6(Ead=-11.19kcal/mol). According to this comparison aniline molecule with Ead=-47.55 kcal/mol has the most adsorption energy among all molecules. Calculations showed that when the nanotube was doped by Si and Al atoms, the amount of HOMO/LUMO energy gap (Eg) reduced significantly. This reduced showed that BNNT is a suitable semiconductor after doping and the doped BNNT in the presence of those gases generates an electrical signal and therefore can be used potentially for gas sensors. Recent researches demonstrate that Boron nitride nanotube is a suitable adsorbent for detection and separation of those compounds.
    Keywords: Sensor, Nanotube, DFT, BNNT
  • Rehab G. Elsharkawy * Pages 99-114
    The efficiency and performance of supported melamine/ copper complexes, S/[CuCl2(Mel)2].2MeOH, as a new adsorbent, for the adsorptive removal of Indigo Carmine (IC) from aqueous solutions, has been evaluated with respect to several experimental conditions including contact time, initial IC concentration, temperature and adsorbent dosage. The maximum removal percentage (approximately 84%) was observed when used 0.05 g/L of S/[CuCl2(Mel)2].2MeOH, 1.5 x 10-5mol/L of initial IC concentration and contact time of 15min. The experimental data were analyzed by the Langmuir, Freundlich, and Tempkin isotherm models. The monolayer adsorption capacity of S/[CuCl2(Mel)2].2MeOHwas found to be 16.8 x 10-3mol/g by using Langmuir isotherm model. The calculation of the thermodynamic parameters such as Gibbs free energy, entropy and enthalpy changes of the ongoing adsorption process indicated the feasibility and endothermic nature of IC adsorption. The kinetics study suggested that the adsorption of IC onto S/[CuCl2(Mel)2].2MeOH proceeds according to the pseudo-second-order model.
    Keywords: Melamine complexes, characterization, Removal, Adsorption, indigo Carmine
  • Abrar Muslim * Pages 115-127
    This study proposed a novel method for preparing activated carbon from Australian Pine cones (APCs) to optimize Pb(II) adsorption. Based on an analysis conducted, the APCs dried powder consisted of approximately 51.32 wt% of cellulose and 21.15 wt% of lignin on average. Experiments in batch mode at 100-rpm stirring speed, pH 4.7 (± 0.3) and 27 oC (± 2 oC) were conducted to obtain the maximum adsorption capacity of Australian Pine cones activated carbon(the APCs AC) over the independent variables of contact time, initial Pb(II) concentration in solution, the concentration of NaOH activator and Pulsed Microwave Heating (PMH). As the result, the maximum Pb(II) adsorption capacity was obtained when using the APCs AC with 1 M NaOH and the PMH activation. It follows Langmuir Isotherm Model (LIM) and the pseudo-second-order kinetics model (PSOKM) with the correlation coefficients (R2) being 0.993 and 1, respectively. The LIM maximum Pb(II) adsorption capacity was 166.667 mg/g, the PSOKM maximum equilibrium Pb(II) adsorption capacity was 151.515 mg/g reached in 120-min contact time, and the PSOKM kinetics constant was 0.295 g/mg.min for 1571.89 mg/L of initial Pb(II) concentration. This optimum condition was reasonable because the PMH resulted from the dominant active site of the functional group of hydroxyl on the APCs AC for Pb(II) adsorption as shown by Fourier Transform Infrared Spectroscopy analysis, and more pores were shown in Scanning Electron Microscopy (SEM) analysis.
    Keywords: Australian pine cones, Adsorption, isotherm, Kinetics, Pulsed microwave heating, Optimization
  • Milad Goleij, Hossein Fakhraee* Pages 129-141
    The present investigation describes the evaluation of feasibility of MWCNT-Fe3O4 nanocomposite toward adsorptive removal of Co(II) and Pb(II) from aqueous solution in batch mode. The Fe3O4–MWCNT hybrid was prepared using a simple one-pot strategy via in situ growth of Fe3O4 magnetic nanoparticles onto the surface of the MWCNTs. The Fe3O4–MWCNT hybrid was characterized by X-ray diffractometry and Field Emission Scanning Electron Microscopy (FESEM).
    A Response Surface Methodology (RSM) with a Central Composite Design (CCD) was employed to evaluate the effects of solution pH, contact time, temperature, initial heavy metal concentration and adsorbent dosage on the removal efficiency of the heavy metals. Results of analysis of variance (ANOVA) showed that the initial metal concentration and absorbent dosage and their interaction effect were the most significant parameters for Co(II) ion removal. Adsorbent dosage, pH and initial metal concentration had significant influences on the removal efficiency of Pb(II) ions. The optimum pH, time, temperature, initial concentration of metals and adsorbent dosage were found to be 6.5,25 min, 40 °C, 35 mg/L, and 48.3 mg/50mL, respectively. Maximum removal of Pb(II) and Co(II) in optimum condition was 90.2 and 79.34% respectively. Results indicated that nanocomposite can be used as an effective adsorbent for effluent decontamination especially in Pb–Co bearing wastewaters. The equilibrium data were well fitted by the Langmuir model. The removal mechanism of metal ions followed adsorption and ion exchange processes.
    Keywords: Nanocomposite, Removal, Cobalt, Lead, RSM
  • Pradip Mandal *, Huda Nasir Pages 143-148
    The aim of this study is to explore the capability of subcritical methanol to reduce the acidity of naphthenic acids and to determine reaction kinetics for large-scale reactor design.The experiments were carried out in a 25 mL autoclave reactor (China) at temperatures of 70-120oC, Methanol Partial Pressures (MPPs) of 0.1-1.5 MPa, and reaction times of 0-60 min. The total acid number content of the samples was analyzed using ASTM D 974 techniques. Experimental results reveal that total acid number reduction of naphthenic acids increased with increasing reaction temperature, MPP, and reaction time. Approximately 74.20% total acid number was reduced at a temperature of 120oC, a MPP of 1 MPa, and a reaction time of 60 min. Experimental data revealed that total acid number removal reaction kinetics followed second-order kinetics with an activation energy of 11.27 kcal/mol. Therefore, subcritical methanol is able to reduce the total acid number of naphthenic acids without the addition of any catalyst.
    Keywords: Naphthenic acid, Subcritical methanol, Total acid number, Petroleum oil, Reaction kinetics
  • Mehdi Asadollahzadeh *, Rezvan Torkaman, Meisam Torab-Mostaedi Pages 149-161
    The aim of this study is to explore the capability of subcritical methanol to reduce the acidity of naphthenic acids and to determine reaction kinetics for large-scale reactor design.The experiments were carried out in a 25 mL autoclave reactor (China) at temperatures of 70-120oC, Methanol Partial Pressures (MPPs) of 0.1-1.5 MPa, and reaction times of 0-60 min. The total acid number content of the samples was analyzed using ASTM D 974 techniques. Experimental results reveal that total acid number reduction of naphthenic acids increased with increasing reaction temperature, MPP, and reaction time. Approximately 74.20% total acid number was reduced at a temperature of 120oC, a MPP of 1 MPa, and a reaction time of 60 min. Experimental data revealed that total acid number removal reaction kinetics followed second-order kinetics with an activation energy of 11.27 kcal/mol. Therefore, subcritical methanol is able to reduce the total acid number of naphthenic acids without the addition of any catalyst.
    Keywords: Kühni Column, Overall Mass Transfer Coefficients, Mass Transfer Direction, Sherwood Number
  • Zeynep Cierolu *, . smail Kirbalar, Selin ahing., Ouml, Kben K., Ouml, PrUcU Pages 163-171
    The present article includes the Ultrasound-Assisted Extraction (UAE) of Citrus unsiu Marc. leaves rich in polyphenols. The best possible combinations of solvent, pH of the media, solvent/solid ratio, extraction time, extraction temperature and particle size were obtained for the maximum extraction of Total Phenolic Compounds (TPC) and Total Flavonoid Compounds (TFC) by using One-Factor-at-a-Time (OFAT) approach. The optimum extraction conditions of TPC were as follows: pH 4 in water; solvent/solid ratio of 20:1; extraction time, 54 min; and extraction temperature, 53ºC. On the other hand, pH 2 in water, solvent/solid ratio of 42:1, 48 min and 58ºC were found to be the optimal conditions for the extraction of TFC. The solvent selection was the most effective parameter for the related system. Additionally, several kinetic models (Film theory, Peleg model, first-order mechanism model and second order mechanism model) were employed to examine the kinetics of UAE.
    Keywords: Citrus unshiu Marc. leaves, Ultrasound, assisted extraction, Surfactant, One, factor, at, a, time optimization, Total phenolic content, Total flavonoid content
  • Rahim Shamsoddini * Pages 173-183
    Fluid mixing is a crucial and challenging process for microfluidic systems, which are widely used in biochemical processes. Because of their fast performance, active micromixers that use stirrer blades are considered for biological applications. In the present study, by using a robust and convenient Incompressible Smoothed Particle Hydrodynamics (ISPH) method, miscible mixing within a two-blade micromixer is investigated. The problem discussed herein is represented by an active micromixer comprising two stir-bars that rotate to mix the fluids. Because of its Lagrangian nature, Smoothed Particle Hydrodynamics is an appropriate and convenient method for simulating moving boundary problems and tracking the particles in the mixing process. Previous investigations have been carried out for mixing flow for a low Schmidt number. However, a low Schmidt number is barely applicable for liquid mixing. Hence, in the present study, the Schmidt number is considered to be Sc=1000. The present results show that the two-blade micro-channel mixer considerably improves the mixing rate in comparison with the one-blade micro-channel mixer.
    Keywords: Micromixer, SPH, Two, stirrer