Fariba Oulad; Sirus Zinadini; Ali Akbar Zinatizadeh; Ali Ashraf Derakhshan
Abstract
The main purpose of this study was to investigate the effect of different operational parameters on performance and fouling trends of unfilled- polyethersulfone, 0.5 wt.% boehmite-polyethersulfone, tannic acid coated boehmite-polyethersulfone nanofiltration membranes during filtration of Licorice aqueous ...
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The main purpose of this study was to investigate the effect of different operational parameters on performance and fouling trends of unfilled- polyethersulfone, 0.5 wt.% boehmite-polyethersulfone, tannic acid coated boehmite-polyethersulfone nanofiltration membranes during filtration of Licorice aqueous solution as model foulant. The impact of hydrodynamic conditions (such as transmembrane pressure and cross-flow velocity) and feed composition on permeation, fouling trends and rejection capability were evaluated using lab-scale cross-flow filtration set-up. The applied transmembrane pressure and cross-flow velocity were various in range of 6-12 bar and 0.5-2.5 cm/s, respectively. The results indicated that although, increasing of operational pressure and cross-flow velocity can enhance the permeability and rejection capability of NF membranes also incur appearance of the more severe fouling phenomenon. The least fouling for NF membranes was occurred at the lowest licorice concentration of 0.1 g/l. The rejection percentage of unfilled and embedded nanofiltration polyethersulfone membranes was more than 92 %.
Fariba Oulad; Sirus Zinadini; Ali Akbar Zinatizadeh; Ali Ashraf Derakhshan
Abstract
The filtration performance of coupling modified polyethersulfone (PES) membrane by coupling diazonium reaction and 25 wt.% aniline modified polyethersulfone (APES /PES) blended membrane by radically diazonium reaction for treating of licorice aqueous solution was verified systematically and compared ...
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The filtration performance of coupling modified polyethersulfone (PES) membrane by coupling diazonium reaction and 25 wt.% aniline modified polyethersulfone (APES /PES) blended membrane by radically diazonium reaction for treating of licorice aqueous solution was verified systematically and compared to bare NF PES membrane. The effect of operational pressure and cross-flow velocity on permeation flux and rejection were evaluated. All experiments were employed in a lab scale cross-flow filtration equipment with effective area of 40 cm2. The applied operational pressure and cross-flow velocity were diverse from 6 to 12 bar and 0.5 to 2.5 cm/s respectively. The obtained results of rejection for licorice aqueous solution were between 84.4% to 99.2%. The durability and antifouling performance of membranes were assessed through long-term filtration of licorice aqueous solution.
Batool Shahroie; Laleh Rajabi; Ali Ashraf Derakhshan
Volume 3, Issue 2 , December 2016, , Pages 277-280
Golshan Moradi; Farzad Dabirian; Laleh Rajabi; Ali Ashraf Derakhshan
Volume 2, Issue 2 , December 2015, , Pages 170-175
Abstract
Novel electrospun polyacrylonitrile (PAN) nanofiber mats and PAN fabric were chemically modified by dissolved anhydrous stannous chloride diethyl ether saturated with hydrogen chloride to contain aldehyde groups on their surfaces, which are suitable for ammonium adsorption due to their high adsorption ...
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Novel electrospun polyacrylonitrile (PAN) nanofiber mats and PAN fabric were chemically modified by dissolved anhydrous stannous chloride diethyl ether saturated with hydrogen chloride to contain aldehyde groups on their surfaces, which are suitable for ammonium adsorption due to their high adsorption affinity for NH4+ ion. Scanning electron microscopy (SEM), and Fourier-transform infrared spectra (FT-IR) were employed to characterize the prepared adsorbents. FT-IR spectra of these adsorbents confirmed that aldehyde groups are successfully formed on the surface of these chemically modified adsorbents. The aldehydic electrospun PAN nanofiber mats and aldehydic PAN fabric were assessed for their chelating property with NH4+ ion from aqueous solution. The effects of contact time on the amounts of ammonium adsorbed into the prepared adsorbents were also studied. Results revealed that ammonium removal increased by increasing contact time which finally reached equilibrium at about 3.5 h and 4 h for aldehydic electrospun PAN nanofiber mats and aldehydic PAN fabric, respectively. The adsorption performance of these prepared adsorbents for ammonium adsorption with initial ammonium concentration of 300 ppm via isotherm studies was investigated. The maximum ammonium removal efficiency (% R) was 48.33 and 70 for aldehydic electrospun PAN nanofiber mats and PAN fabric, respectively. Results indicated that the adsorption of ammonium by both prepared adsorbents followed Langmuir isotherm.
