فهرست مقالات dimethyl ether

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  1 - The effect of polymer molar mass on the aqueous two-phase system containing Poly ethylene glycol dimethyl ether and ammonium sulphate and its application of this system in partitioning of iodine
  Mohammed Taghi Zafarani–Moattar Hemayat Shekaari Tohid Hashemzadeh
  The partitioning of iodide was studied in an aqueous two phase system (ATPS) comprised of ammonium sulphate, poly ethylene glycol dimethyl ether (PEGDME), and water at 298.15 K. To investigate the effect of molar mass of the polymer on the tie-line, similar measurements چکیده کامل

  The partitioning of iodide was studied in an aqueous two phase system (ATPS) comprised of ammonium sulphate, poly ethylene glycol dimethyl ether (PEGDME), and water at 298.15 K. To investigate the effect of molar mass of the polymer on the tie-line, similar measurements were also made at T=298.15 K on this two phase system consisting of the PEGDME with molar masses of 250, 500 and 2000 g.mol-1. Finally the effect of molar mass of polymer on the binodal of {PEGDME + ammonium sulphate +water} was studied by measuring liquid-liquid equilibrium at T= 298.15 K for three different molar masses. The experimental binodal data were described using two empirical nonlinear three parameter expressions developed by Merchuk and Zafarani Moattar et al. The increase in the polymer molar mass provides ATPS with larger biphasic region. The tie-line compositions were estimated and correlated using the Othmer–Tobias and Bancroft and Setschenow type equations. In addition the partitioning behavior of the iodine molecule on the investigated aqueous two-phase system was studied. پرونده مقاله
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  2 - Dehydration of Methanol to Dimethyl Ether using Y Zeolite Nano-catalyst Prepared via Hydrothermal Technique
  Hamid Ghaffari Mohamad Mahdi Zerafat Sahar Foorginezhad
  10.22034/jna.2022.1925780.1249
  Y-type zeolite can be considered among the most applied zeolites at industrial scale especially for catalytic transformations among various zeolites. Various synthesis techniques are employed to produce zeolite Y among which hydrothermal technique is considered as the m چکیده کامل

  Y-type zeolite can be considered among the most applied zeolites at industrial scale especially for catalytic transformations among various zeolites. Various synthesis techniques are employed to produce zeolite Y among which hydrothermal technique is considered as the most prevalent. In this study, synthesis of Y-type nano-zeolite was investigated through template-free hydrothermal technique. At various temperatures and aging times, zeolite Y was synthesized in the 10-30 nm size range with a first stage temperature of 25 °C and 87 °C as the second stage temperature. The as-synthesized zeolite was characterized using X-ray diffraction (XRD), Fourier-Transform Infrared (FTIR) spectroscopy, Field-Emission scanning electron microscopy (FE-SEM), Nitrogen adsorption–desorption, Transmission electron microscopy (TEM), and NH3-TPD and utilized as the nano-catalyst in methanol to dimethyl ether (DME) conversion process. Based on the results, at 400 °C, 53.7 % conversion to DME was obtained with 100% purity using hydrogen form of zeolite Y (H-Y) nano-catalyst. Natural zeolite is also considered as a proper additive to economize the product. پرونده مقاله
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  3 - Montmorillonite-Zirconium Phosphate Catalysts for Methanol Dehydration
  Hasanudin Hasanudin Wan Asri Qodria Putri Zainal Fanani David Bahrin Tuty Agustina Karna Wijaya
  10.30495/ijc.2022.1960655.1942
  Modification of sodium montmorillonite was conducted using zirconium phosphate. The effect of a series of phosphate precursors such as dihydrogen phosphate, diammonium hydrogen phosphate, and sodium phosphate was observed. The catalyst was used in the conversion of meth چکیده کامل

  Modification of sodium montmorillonite was conducted using zirconium phosphate. The effect of a series of phosphate precursors such as dihydrogen phosphate, diammonium hydrogen phosphate, and sodium phosphate was observed. The catalyst was used in the conversion of methanol dimethyl ether using 1 g of catalyst at a temperature range of 150-350 ˚C with a Liquid Hourly Space Velocity (LHSV) monitored to 2.54 h−1 and N2 as carrier gas. The product was analyzed directly with a reactor system connected to gas chromatography. The X-ray diffraction (XRD), Scanning electron microscope-energy dispersive X-ray (SEM-EDX), N2 adsorption-desorption, and Temperature-programmed desorption of ammonia (NH3-TPD) were utilized to characterize the catalyst. The characterization showed that the modified sodium montmorillonite-zirconium phosphate was successfully synthesized. The study showed that modified montmorillonite using zirconium phosphate significantly increased the catalytic activity of sodium montmorillonite by providing medium and strong acid sites also increased the surface area. The modified sodium montmorillonite-zirconium phosphate from dihydrogen phosphate precursor exhibited the highest catalytic activity with the methanol conversion of 96.76%, dimethyl ether selectivity of 96.8%, and dimethyl ether yield of 93.67%, whereas the modified sodium montmorillonite-zirconium phosphate from diammonium hydrogen phosphate showed good stability towards methanol conversion. پرونده مقاله