فهرست مطالب

Applied Chemical Research - Volume:12 Issue: 3, Summer 2018

Journal of Applied Chemical Research
Volume:12 Issue: 3, Summer 2018

  • تاریخ انتشار: 1397/04/04
  • تعداد عناوین: 8
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  • Benjamin Olawale Orimolade *, Folahan Amoo Adekola, Aderonke Aminat Mohammed, Azeez Olayiwola Idris, Oluwaseyi Damilare Saliu, Taofeek Yusuf Pages 8-21
    This study evaluates the adsorption of bisphenol-A (BPA) from aqueous solutions using nanosilica obtained from rice husk. Nanosilica (79 nm) was extracted from acid and thermal treated rice husk waste. The rice husk nanosilica (RHS) was fully characterized through X-Ray Diffraction Spectroscopy (XRD), Scanning Electron Microscopy (SEM), X-Ray Fluorescence Spectroscopy (XRF) and Fourier Transmittance Infrared Spectroscopy (FTIR). The spectroscopic analyses results revealed that the rice husk ash contains large fraction of amorphous silica. Batch adsorption experiments were carried out on BPA as a function of initial concentration, contact time, pH, adsorbent dosage and temperature. The maximum amount of BPA adsorbed was 4.267 mg/g with an optimum contact time of 45 min for 50 mg/L BPA solution at pH 8. The adsorption data were analyzed with adsorption isotherms and fitted best into the Langmuir model with R2 value of 0.994. The adsorption process followed the pseudo second order kinetics and was exothermic while the negative value of Gibbs free energy obtained revealed that the process is feasible at lower temperature.
    Keywords: Bisphenol-A, adsorption, rice-husk, Isotherm, Silica
  • Maasoomeh Ghasemi *, Ali Moghimi, Mohammad-Ali Karimi, Shahla Mozaffari Pages 22-30
    A solid phase extraction procedure for simultaneous separation and preconcentration of trace amounts of Cu ion from various real samples prior to its determination by flame atomic absorption spectrometry has been developed. The proposed method is based on the utilization of multiwalled carbon nanotube in combination with Cupferron ligand as a solid phase extractant. The influences of the analytical parameters, including pH, amounts of ligand and adsorbent, sample volume, volume and concentration of eluent, flow rates of solution and , interference effects from the foreign metal ions were investigated for the optimum recoveries of the analyte ion. The optimum pH for the separation of Cu ion on the new sorbent was . . The relative standard deviation (RSDs) and the recoveries of standard addition for this method were lower than 5 % and 95-100 %, respectively. A sample volume of 200 mL resulted in a preconcentration factor of 100. The proposed procedure was successfully applied to the determination of copper in various real samples with satisfactory results.
    Keywords: Solid phase extraction, Flame atomic absorption spectrometry, heavy metals, Multiwalled carbon nanotubes, Cupferron ligand, Preconcentration
  • Syedeh Fatemeh Hosseinzadeh, Masoud Mokhtary * Pages 31-41
    3-Carboxy-1-sulfopyridin-1-ium chloride ([CPySO3H]) as a novel ionic organocatalyst for the condensation of aldehydes and 2-methylindole to synthesize bis(2-methyl-1H-indole) derivatives in acetonitrile at room temperature has been developed. Some tetrakis (2-methyl-1H indole) derivatives have also been synthesized by the reaction of 2,2'-(butane-1,4- diylbis(oxy))dibenzaldehyde and 2-methylindole or indole in the presence of chlorosulfonic acid immobilized on nicotinic acid ([CPySO3H]) at room temperature. All products formed in excellent yields over short reaction times under mild and environmentally friendly conditions. This methodology offers significant improvements for the synthesis of bis(2-methyl-1H-indole) derivatives with regard to the yield of products, simplicity in operation and reusability of the catalyst.
    Keywords: Bis(2-methyl-1H-indole), Chlorosulfonic acid, 3-Carboxy-1-sulfopyridin-1-ium, Tetrakis (2-methyl-1H-indole), Nicotinic acid
  • Elham Eslami *, Fatemeh Farjami Pages 42-52
    The combination of multi-walled carbon nanotubes and ionic liquid 1-octylpyridinium hexa flourophosphate (OPFP) yields a carbon nanocomposite (MWCNT-CILE) that can be well used as electrode for electrocatalytic oxidation of venlafaxine (VEN). The influence of various experimental parameters including pH of the solution, the amount of multi-walled carbon nanotube used for the modification of the carbon ionic liquid electrode (CILE), accumulation potential, accumulation time and scan rate on the voltammetric responses of venlafaxine were all investigated in the present research. The oxidation peak potential of venlafaxine appeared at 640 mV at the proposed electrode that is about 150 mV lower than the peak potential at traditional carbon paste electrodes (CPE). The oxidation is irreversible and exhibits adsorption controlled behavior. Under the optimum conditions, the anodic peak current has a linear relationship with venlafexine concentration in the range of 10.0 to 500.0μM. The detection limit (three times signal-to noise ratio) of 0.47μM was found. Finally, the proposed sensor has the features of being sensitive, reproducible, easily renewable and cost effective which might suggest promising applications for determination of VEN in pharmaceiutical formualations as well as blood serum and urine samples.
    Keywords: Electrochemistry, Ionic liquid, Multi-walled carbon nanotube, Sensor, Venlafaxine
  • Mohammadjavad Taghizadeh *, Mehdi Didwar Pages 53-64
    Different sulfides were oxidized to the corresponding sulfoxides, which is useful in drug industries and important in biological activities, with a novel magnetically separable catalyst consisting of tungstic acid supported on silica coated magnetic nanoparticles in water as a green solvent in a good to excellent yield without any over oxidation to sulfones in a simple, selective, and eco friendly way. The catalyst can be separated from reaction condition using an external magnetic field and reused for several times as its first structure. Using some different microscopic and spectroscopic techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), and EDX spectroscopy.
    Keywords: Sulfoxide, tungstic acid, oxidation, Heterogeneous, catalyst, selective oxidation
  • Sayed Rasul Shafe Mehrabadi, Bahareh Sadeghi *, Saleheh Zavar Pages 65-73
    Nano-rice bran/TiCl4has been prepared from rice bran and TiCl4 in n-hexane as solvent. Thennanorice bran/TiCl4 has been introduced as a novel catalystfor the three component synthesis of pyrano [3,2-b] pyransfrom the simple one-pot reactionbetweenaryl aldehydes,cyanoacetamide and kojic acid.Cleanliness, an eco-friendly catalyst, simple methodology, short time, and excellent yields of products are some advantages of this method.
    Keywords: Nano-rice bran-TiCl4, Pyrano [3, 2-b] pyrans, Cyanoacetamide, Kojic acid, Aryl aldehydes
  • Mohsen Kasaeezadeh *, Alireza Azimi Pages 74-87
    One of the main problems in oil recovery via the gas injection is the formation of hydrates in the lines. In order to prevent the formation of hydrate in these lines, which leads to the blockage and sometimes explosion, at first, the equilibrium formation conditions must be determined and then to prevent its formation by changing the thermodynamic conditions or by adding the inhibitors. In this research, the hydrate formation for a natural gas sample has been studied under the various thermodynamic conditions. For this purpose, a gas sample was taken from the natural gas transmission lines. Then, the conditions for the formation of gas hydrates were determined from the experimental equations. Also, by constructing and launching a laboratory system, the experiments were carried out using the Isochoric method and the hydrate formation conditions were determined. The experiments were done at a temperature range of 264 to 300 K and a pressure range of 5 to 45 bar in the pure water. The results showed that, with increasing temperature, the equilibrium pressure of the hydrate formation increases and with increasing pressure, the equilibrium temperature of hydrate formation is reduced.
    Keywords: Gas Hydrate, Constant volume size, Equilibrium conditions
  • Soodabe Gharibe * Pages 88-100
    The ZnO/SiO2 semiconductor nanophotocatalysis was synthesized via sol-gel method. Also, the platinum particles were loaded on the ZnO/SiO2 nanoparticles by photoreductive method. The structure of catalyst was confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM) andfourier transform infrared spectroscopy (FT-IR). The XRD patterns of ZnO particles displayed the nanoparticles have a wurtzite structure (hexagonal phase). The crystallite sizes were calculated using Scheerer’s equation and were around 32nm. For photocatalytic test, decomposition of Malachite Green oxalate (MG), as an organic pollutant was carried out by synthesized catalyst. A comparison of degradation between bare catalyst and platinum loaded ZnO/SiO2nanoparticle under UV-Vis light irradiation shows that the Pt-ZnO/SiO2 photocatalyst is more efficient than ZnO/SiO2 nanoparticles. Also, the activity of ZnO/SiO2nanoparticles in the visible light are minimal, while loading of Pt in zinc oxide network displaced the band gap toward longer wavelengths (visible light) and increased the photocatalysis activity of ZnO/SiO2 in the range of visible light.
    Keywords: Photocatalyst, Malachite Green, UV-Vis, ZnO, Organic pollutants