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Mustafa Ersoz - One of the best experts on this subject based on the ideXlab platform.

  • facilitated transport of cr vi through a novel activated composite membrane containing cyanex 923 as a carrier
    Journal of Membrane Science, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Ali Tor, Ilker Akin, Harun Muslu, Mustafa Ozmen, Mustafa Ersoz
    Abstract:

    Abstract This paper describes the facilitated transport of Cr(VI) through a novel Activated Composite Membrane (ACM) containing Cyanex 923 as a carrier. The ACM was prepared by immobilization of the Cyanex 923 on a polysulfone support by means of interfacial polymerisation. The prepared ACM was characterized by using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques and contact angle measurements. The effect of Feed Phase composition, carrier concentration of the casting solution and stripping Phase composition on the transport of Cr(VI) was investigated. When the Feed Phase contained 1 × 10 −3  M Cr(VI) at pH 1.0, 99% of Cr(VI) was transported through the ACM (prepared with 3% carrier solution) by using 1 M NaOH as a stripping Phase. Furthermore, Cr(VI) was preferably transported in the presence of various metal ions (i.e., Cr(III), Ni(II), Cu(II), Zn(II), Cd(II), Co(II), etc.) and sulphate and nitrate ions had no negative effect on the transport of Cr(VI). The results also showed that transport efficiency of the ACM was reproducible and it could be efficiently used in the long-term separation processes instead of supported liquid membrane (SLM).

  • facilitated transport of cr iii through activated composite membrane containing di 2 ethylhexyl phosphoric acid dehpa as carrier agent
    Journal of Hazardous Materials, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Mustafa Ersoz
    Abstract:

    Abstract The facilitated transport of chromium(III) through activated composite membrane (ACM) containing di-(2-ethylhexyl) phosphoric acid (DEHPA) was investigated. DEHPA was immobilised by interfacial polymerisation on polysulfone layer which was deposited on non-woven fabric by using spin coater. Then, ACM was characterised by using scanning electron microscopy (SEM), contact angle measurements and atomic force microscopy (AFM). Initially, batch experiments of liquid–liquid distribution of Cr(III) and the extractant (DEHPA) were carried out to determine the appropriate pH of the Feed Phase and the results showed that maximum extraction of Cr(III) was achieved at a pH of 4. It was also found that Cr(III) and DEHPA reacted in 1/1 molar ratio. The effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in ACM) concentrations were investigated. DEHPA concentration varies from 0.1 to 1.0 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.8 M. It was also observed that the transport of Cr(III) through the ACM tended to increase with Cr(III) and HCl concentrations. The stability of ACM was also confirmed with replicate experiments.

  • facilitated transport of cr iii through activated composite membrane containing di 2 ethylhexyl phosphoric acid dehpa as carrier agent
    Journal of Hazardous Materials, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Mustafa Ersoz
    Abstract:

    Abstract The facilitated transport of chromium(III) through activated composite membrane (ACM) containing di-(2-ethylhexyl) phosphoric acid (DEHPA) was investigated. DEHPA was immobilised by interfacial polymerisation on polysulfone layer which was deposited on non-woven fabric by using spin coater. Then, ACM was characterised by using scanning electron microscopy (SEM), contact angle measurements and atomic force microscopy (AFM). Initially, batch experiments of liquid–liquid distribution of Cr(III) and the extractant (DEHPA) were carried out to determine the appropriate pH of the Feed Phase and the results showed that maximum extraction of Cr(III) was achieved at a pH of 4. It was also found that Cr(III) and DEHPA reacted in 1/1 molar ratio. The effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in ACM) concentrations were investigated. DEHPA concentration varies from 0.1 to 1.0 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.8 M. It was also observed that the transport of Cr(III) through the ACM tended to increase with Cr(III) and HCl concentrations. The stability of ACM was also confirmed with replicate experiments.

  • removal of nitrate from the aqueous Phase by donnan dialysis
    Desalination, 2009
    Co-Authors: Ozlem Altintas, Yunus Cengeloglu, Mustafa Ersoz
    Abstract:

    The removal of nitrate ions through SB-6407 and Neosepta AMX anion exchange membranes has been studied under Donnan dialysis conditions as a function of receiver Phase concentration and co-existence anions in the Feed Phase. For both membranes, it was observed that the transport of nitrate increased with increase of the receiver Phase concentration and decreased in the presence of co-existence anions in Feed Phase. It was also observed that the nitrate transport efficiency of the SB-6407 was higher than that of the Neosepta AMX membrane. The transport of nitrate ions was correlated with the flux data and explained according to the membrane structure.

  • facilitated transport of cr iii through polymer inclusion membrane with di 2 ethylhexyl phosphoric acid dehpa
    Journal of Membrane Science, 2009
    Co-Authors: Ali Tor, Gulsin Arslan, Yunus Cengeloglu, Harun Muslu, Ahmet Celiktas, Mustafa Ersoz
    Abstract:

    In this study, transport of Cr(III) through polymer inclusion membrane (PIM) with di(2-ethylhexyl)phosphoric acid (DEHPA) as carrier was reported. First, PIM was characterized by using FTIR and atomic force microscopy (AFM) techniques and contact angle measurements. Then, the effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in membrane) concentrations on the transport were investigated. DEHPA concentration varies from 0.25 to 0.5 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.4 M. It was also observed that the transport of Cr(III) through the PIM tended to increase with Cr(III) and HCl concentrations. According to the competitive transport of Cr(III), Cu(II) and Ni(II) through the PIM, the transport selectivity order was found as Cr(III) ≈ Cu(II) > Ni(II). The result from the transport of Cr(III) mixed with Cr(VI) also showed that flux of Cr(III) was not influenced by the presence of Cr(VI) in Feed Phase and no Cr(VI) transport through the PIM was determined. PIM had lower experimental Cr(III) flux than those of supported liquid membrane (SLM) and activated composite membrane (ACM) under the same experimental conditions. However, long-term stability of PIM and small difference between normalized flux for PIM and experimental SLM flux indicated that PIM could replace SLM for practical applications.

Yunus Cengeloglu - One of the best experts on this subject based on the ideXlab platform.

  • facilitated transport of cr vi through a novel activated composite membrane containing cyanex 923 as a carrier
    Journal of Membrane Science, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Ali Tor, Ilker Akin, Harun Muslu, Mustafa Ozmen, Mustafa Ersoz
    Abstract:

    Abstract This paper describes the facilitated transport of Cr(VI) through a novel Activated Composite Membrane (ACM) containing Cyanex 923 as a carrier. The ACM was prepared by immobilization of the Cyanex 923 on a polysulfone support by means of interfacial polymerisation. The prepared ACM was characterized by using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques and contact angle measurements. The effect of Feed Phase composition, carrier concentration of the casting solution and stripping Phase composition on the transport of Cr(VI) was investigated. When the Feed Phase contained 1 × 10 −3  M Cr(VI) at pH 1.0, 99% of Cr(VI) was transported through the ACM (prepared with 3% carrier solution) by using 1 M NaOH as a stripping Phase. Furthermore, Cr(VI) was preferably transported in the presence of various metal ions (i.e., Cr(III), Ni(II), Cu(II), Zn(II), Cd(II), Co(II), etc.) and sulphate and nitrate ions had no negative effect on the transport of Cr(VI). The results also showed that transport efficiency of the ACM was reproducible and it could be efficiently used in the long-term separation processes instead of supported liquid membrane (SLM).

  • facilitated transport of cr iii through activated composite membrane containing di 2 ethylhexyl phosphoric acid dehpa as carrier agent
    Journal of Hazardous Materials, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Mustafa Ersoz
    Abstract:

    Abstract The facilitated transport of chromium(III) through activated composite membrane (ACM) containing di-(2-ethylhexyl) phosphoric acid (DEHPA) was investigated. DEHPA was immobilised by interfacial polymerisation on polysulfone layer which was deposited on non-woven fabric by using spin coater. Then, ACM was characterised by using scanning electron microscopy (SEM), contact angle measurements and atomic force microscopy (AFM). Initially, batch experiments of liquid–liquid distribution of Cr(III) and the extractant (DEHPA) were carried out to determine the appropriate pH of the Feed Phase and the results showed that maximum extraction of Cr(III) was achieved at a pH of 4. It was also found that Cr(III) and DEHPA reacted in 1/1 molar ratio. The effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in ACM) concentrations were investigated. DEHPA concentration varies from 0.1 to 1.0 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.8 M. It was also observed that the transport of Cr(III) through the ACM tended to increase with Cr(III) and HCl concentrations. The stability of ACM was also confirmed with replicate experiments.

  • facilitated transport of cr iii through activated composite membrane containing di 2 ethylhexyl phosphoric acid dehpa as carrier agent
    Journal of Hazardous Materials, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Mustafa Ersoz
    Abstract:

    Abstract The facilitated transport of chromium(III) through activated composite membrane (ACM) containing di-(2-ethylhexyl) phosphoric acid (DEHPA) was investigated. DEHPA was immobilised by interfacial polymerisation on polysulfone layer which was deposited on non-woven fabric by using spin coater. Then, ACM was characterised by using scanning electron microscopy (SEM), contact angle measurements and atomic force microscopy (AFM). Initially, batch experiments of liquid–liquid distribution of Cr(III) and the extractant (DEHPA) were carried out to determine the appropriate pH of the Feed Phase and the results showed that maximum extraction of Cr(III) was achieved at a pH of 4. It was also found that Cr(III) and DEHPA reacted in 1/1 molar ratio. The effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in ACM) concentrations were investigated. DEHPA concentration varies from 0.1 to 1.0 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.8 M. It was also observed that the transport of Cr(III) through the ACM tended to increase with Cr(III) and HCl concentrations. The stability of ACM was also confirmed with replicate experiments.

  • removal of nitrate from the aqueous Phase by donnan dialysis
    Desalination, 2009
    Co-Authors: Ozlem Altintas, Yunus Cengeloglu, Mustafa Ersoz
    Abstract:

    The removal of nitrate ions through SB-6407 and Neosepta AMX anion exchange membranes has been studied under Donnan dialysis conditions as a function of receiver Phase concentration and co-existence anions in the Feed Phase. For both membranes, it was observed that the transport of nitrate increased with increase of the receiver Phase concentration and decreased in the presence of co-existence anions in Feed Phase. It was also observed that the nitrate transport efficiency of the SB-6407 was higher than that of the Neosepta AMX membrane. The transport of nitrate ions was correlated with the flux data and explained according to the membrane structure.

  • facilitated transport of cr iii through polymer inclusion membrane with di 2 ethylhexyl phosphoric acid dehpa
    Journal of Membrane Science, 2009
    Co-Authors: Ali Tor, Gulsin Arslan, Yunus Cengeloglu, Harun Muslu, Ahmet Celiktas, Mustafa Ersoz
    Abstract:

    In this study, transport of Cr(III) through polymer inclusion membrane (PIM) with di(2-ethylhexyl)phosphoric acid (DEHPA) as carrier was reported. First, PIM was characterized by using FTIR and atomic force microscopy (AFM) techniques and contact angle measurements. Then, the effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in membrane) concentrations on the transport were investigated. DEHPA concentration varies from 0.25 to 0.5 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.4 M. It was also observed that the transport of Cr(III) through the PIM tended to increase with Cr(III) and HCl concentrations. According to the competitive transport of Cr(III), Cu(II) and Ni(II) through the PIM, the transport selectivity order was found as Cr(III) ≈ Cu(II) > Ni(II). The result from the transport of Cr(III) mixed with Cr(VI) also showed that flux of Cr(III) was not influenced by the presence of Cr(VI) in Feed Phase and no Cr(VI) transport through the PIM was determined. PIM had lower experimental Cr(III) flux than those of supported liquid membrane (SLM) and activated composite membrane (ACM) under the same experimental conditions. However, long-term stability of PIM and small difference between normalized flux for PIM and experimental SLM flux indicated that PIM could replace SLM for practical applications.

Ali Tor - One of the best experts on this subject based on the ideXlab platform.

  • Selectively facilitated transport of Zn(II) through a novel polymer inclusion membrane containing Cyanex 272 as a carrier reagent
    Desalination, 2011
    Co-Authors: Abdurrahman Yilmaz, Gulsin Arslan, Ali Tor, Ilker Akin
    Abstract:

    Abstract This paper describes the selectively facilitated transport of Zn(II) through a novel polymer inclusion membrane (PIM) containing Cyanex 272 as a carrier reagent. The prepared PIM was characterized by using Fourier Transform Infrared (FT-IR) spectroscopy and Atomic Force Microscopy (AFM) techniques and contact angle measurements. The effects of Zn(II) (in Feed Phase), HCl (in stripping Phase) and Cyanex 272 (in membrane) concentrations on the transport were investigated. When the Feed Phase contained 1 × 10 − 4  M Zn (II) at pH 3.4, 99% of Zn(II) was transported through the PIM (prepared with 1.0% carrier solution) by using 0.5 M of HCl as a stripping Phase. Furthermore, Zn(II) was preferably transported in the presence of various metal ions (i.e., Ni(II), Cu(II), Pb(II) and Co(II), etc.). The results also showed that transport efficiency of the PIM was reproducible and it could be efficiently used in the long-term separation processes.

  • facilitated transport of cr vi through a novel activated composite membrane containing cyanex 923 as a carrier
    Journal of Membrane Science, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Ali Tor, Ilker Akin, Harun Muslu, Mustafa Ozmen, Mustafa Ersoz
    Abstract:

    Abstract This paper describes the facilitated transport of Cr(VI) through a novel Activated Composite Membrane (ACM) containing Cyanex 923 as a carrier. The ACM was prepared by immobilization of the Cyanex 923 on a polysulfone support by means of interfacial polymerisation. The prepared ACM was characterized by using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques and contact angle measurements. The effect of Feed Phase composition, carrier concentration of the casting solution and stripping Phase composition on the transport of Cr(VI) was investigated. When the Feed Phase contained 1 × 10 −3  M Cr(VI) at pH 1.0, 99% of Cr(VI) was transported through the ACM (prepared with 3% carrier solution) by using 1 M NaOH as a stripping Phase. Furthermore, Cr(VI) was preferably transported in the presence of various metal ions (i.e., Cr(III), Ni(II), Cu(II), Zn(II), Cd(II), Co(II), etc.) and sulphate and nitrate ions had no negative effect on the transport of Cr(VI). The results also showed that transport efficiency of the ACM was reproducible and it could be efficiently used in the long-term separation processes instead of supported liquid membrane (SLM).

  • facilitated transport of cr iii through polymer inclusion membrane with di 2 ethylhexyl phosphoric acid dehpa
    Journal of Membrane Science, 2009
    Co-Authors: Ali Tor, Gulsin Arslan, Yunus Cengeloglu, Harun Muslu, Ahmet Celiktas, Mustafa Ersoz
    Abstract:

    In this study, transport of Cr(III) through polymer inclusion membrane (PIM) with di(2-ethylhexyl)phosphoric acid (DEHPA) as carrier was reported. First, PIM was characterized by using FTIR and atomic force microscopy (AFM) techniques and contact angle measurements. Then, the effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in membrane) concentrations on the transport were investigated. DEHPA concentration varies from 0.25 to 0.5 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.4 M. It was also observed that the transport of Cr(III) through the PIM tended to increase with Cr(III) and HCl concentrations. According to the competitive transport of Cr(III), Cu(II) and Ni(II) through the PIM, the transport selectivity order was found as Cr(III) ≈ Cu(II) > Ni(II). The result from the transport of Cr(III) mixed with Cr(VI) also showed that flux of Cr(III) was not influenced by the presence of Cr(VI) in Feed Phase and no Cr(VI) transport through the PIM was determined. PIM had lower experimental Cr(III) flux than those of supported liquid membrane (SLM) and activated composite membrane (ACM) under the same experimental conditions. However, long-term stability of PIM and small difference between normalized flux for PIM and experimental SLM flux indicated that PIM could replace SLM for practical applications.

  • removal of fluoride from water using anion exchange membrane under donnan dialysis condition
    Journal of Hazardous Materials, 2007
    Co-Authors: Ali Tor
    Abstract:

    The transport of fluoride through Neosepta-ACM anion-exchange membrane has been studied as a function of Feed Phase and receiver Phase concentration and co-existence anions under Donnan dialysis condition. It was observed that the transport of fluoride was maximum at pH 6 of Feed Phase and at pH 1 of receiver Phase. Moreover, transport of fluoride increased with increase of Feed and receiver Phase concentration and decreased in the presence of other co-existence anions in the Feed Phase. The transport of fluoride was also correlated with the flux data and explained according to structure of membrane.

Gulsin Arslan - One of the best experts on this subject based on the ideXlab platform.

  • Selectively facilitated transport of Zn(II) through a novel polymer inclusion membrane containing Cyanex 272 as a carrier reagent
    Desalination, 2011
    Co-Authors: Abdurrahman Yilmaz, Gulsin Arslan, Ali Tor, Ilker Akin
    Abstract:

    Abstract This paper describes the selectively facilitated transport of Zn(II) through a novel polymer inclusion membrane (PIM) containing Cyanex 272 as a carrier reagent. The prepared PIM was characterized by using Fourier Transform Infrared (FT-IR) spectroscopy and Atomic Force Microscopy (AFM) techniques and contact angle measurements. The effects of Zn(II) (in Feed Phase), HCl (in stripping Phase) and Cyanex 272 (in membrane) concentrations on the transport were investigated. When the Feed Phase contained 1 × 10 − 4  M Zn (II) at pH 3.4, 99% of Zn(II) was transported through the PIM (prepared with 1.0% carrier solution) by using 0.5 M of HCl as a stripping Phase. Furthermore, Zn(II) was preferably transported in the presence of various metal ions (i.e., Ni(II), Cu(II), Pb(II) and Co(II), etc.). The results also showed that transport efficiency of the PIM was reproducible and it could be efficiently used in the long-term separation processes.

  • facilitated transport of cr vi through a novel activated composite membrane containing cyanex 923 as a carrier
    Journal of Membrane Science, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Ali Tor, Ilker Akin, Harun Muslu, Mustafa Ozmen, Mustafa Ersoz
    Abstract:

    Abstract This paper describes the facilitated transport of Cr(VI) through a novel Activated Composite Membrane (ACM) containing Cyanex 923 as a carrier. The ACM was prepared by immobilization of the Cyanex 923 on a polysulfone support by means of interfacial polymerisation. The prepared ACM was characterized by using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques and contact angle measurements. The effect of Feed Phase composition, carrier concentration of the casting solution and stripping Phase composition on the transport of Cr(VI) was investigated. When the Feed Phase contained 1 × 10 −3  M Cr(VI) at pH 1.0, 99% of Cr(VI) was transported through the ACM (prepared with 3% carrier solution) by using 1 M NaOH as a stripping Phase. Furthermore, Cr(VI) was preferably transported in the presence of various metal ions (i.e., Cr(III), Ni(II), Cu(II), Zn(II), Cd(II), Co(II), etc.) and sulphate and nitrate ions had no negative effect on the transport of Cr(VI). The results also showed that transport efficiency of the ACM was reproducible and it could be efficiently used in the long-term separation processes instead of supported liquid membrane (SLM).

  • facilitated transport of cr iii through activated composite membrane containing di 2 ethylhexyl phosphoric acid dehpa as carrier agent
    Journal of Hazardous Materials, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Mustafa Ersoz
    Abstract:

    Abstract The facilitated transport of chromium(III) through activated composite membrane (ACM) containing di-(2-ethylhexyl) phosphoric acid (DEHPA) was investigated. DEHPA was immobilised by interfacial polymerisation on polysulfone layer which was deposited on non-woven fabric by using spin coater. Then, ACM was characterised by using scanning electron microscopy (SEM), contact angle measurements and atomic force microscopy (AFM). Initially, batch experiments of liquid–liquid distribution of Cr(III) and the extractant (DEHPA) were carried out to determine the appropriate pH of the Feed Phase and the results showed that maximum extraction of Cr(III) was achieved at a pH of 4. It was also found that Cr(III) and DEHPA reacted in 1/1 molar ratio. The effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in ACM) concentrations were investigated. DEHPA concentration varies from 0.1 to 1.0 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.8 M. It was also observed that the transport of Cr(III) through the ACM tended to increase with Cr(III) and HCl concentrations. The stability of ACM was also confirmed with replicate experiments.

  • facilitated transport of cr iii through activated composite membrane containing di 2 ethylhexyl phosphoric acid dehpa as carrier agent
    Journal of Hazardous Materials, 2009
    Co-Authors: Gulsin Arslan, Yunus Cengeloglu, Mustafa Ersoz
    Abstract:

    Abstract The facilitated transport of chromium(III) through activated composite membrane (ACM) containing di-(2-ethylhexyl) phosphoric acid (DEHPA) was investigated. DEHPA was immobilised by interfacial polymerisation on polysulfone layer which was deposited on non-woven fabric by using spin coater. Then, ACM was characterised by using scanning electron microscopy (SEM), contact angle measurements and atomic force microscopy (AFM). Initially, batch experiments of liquid–liquid distribution of Cr(III) and the extractant (DEHPA) were carried out to determine the appropriate pH of the Feed Phase and the results showed that maximum extraction of Cr(III) was achieved at a pH of 4. It was also found that Cr(III) and DEHPA reacted in 1/1 molar ratio. The effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in ACM) concentrations were investigated. DEHPA concentration varies from 0.1 to 1.0 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.8 M. It was also observed that the transport of Cr(III) through the ACM tended to increase with Cr(III) and HCl concentrations. The stability of ACM was also confirmed with replicate experiments.

  • facilitated transport of cr iii through polymer inclusion membrane with di 2 ethylhexyl phosphoric acid dehpa
    Journal of Membrane Science, 2009
    Co-Authors: Ali Tor, Gulsin Arslan, Yunus Cengeloglu, Harun Muslu, Ahmet Celiktas, Mustafa Ersoz
    Abstract:

    In this study, transport of Cr(III) through polymer inclusion membrane (PIM) with di(2-ethylhexyl)phosphoric acid (DEHPA) as carrier was reported. First, PIM was characterized by using FTIR and atomic force microscopy (AFM) techniques and contact angle measurements. Then, the effects of Cr(III) (in Feed Phase), HCl (in stripping Phase) and DEHPA (in membrane) concentrations on the transport were investigated. DEHPA concentration varies from 0.25 to 0.5 M and it was determined that the transport of Cr(III) increased with the carrier concentration up to 0.4 M. It was also observed that the transport of Cr(III) through the PIM tended to increase with Cr(III) and HCl concentrations. According to the competitive transport of Cr(III), Cu(II) and Ni(II) through the PIM, the transport selectivity order was found as Cr(III) ≈ Cu(II) > Ni(II). The result from the transport of Cr(III) mixed with Cr(VI) also showed that flux of Cr(III) was not influenced by the presence of Cr(VI) in Feed Phase and no Cr(VI) transport through the PIM was determined. PIM had lower experimental Cr(III) flux than those of supported liquid membrane (SLM) and activated composite membrane (ACM) under the same experimental conditions. However, long-term stability of PIM and small difference between normalized flux for PIM and experimental SLM flux indicated that PIM could replace SLM for practical applications.

Joao G Crespo - One of the best experts on this subject based on the ideXlab platform.

  • thiols extraction from jet fuel assisted by ionic liquids in hollow fibre membrane contactors
    Journal of Membrane Science, 2015
    Co-Authors: Ana R Ferreira, Luisa A Neves, Jorge C Ribeiro, Fernando M Lopes, Joao A P Coutinho, Isabel M Coelhoso, Joao G Crespo
    Abstract:

    Abstract This work proposes an alternative technique for the selective extraction of thiols from a “jet-fuel” model stream, using the 1-ethyl-3-methylimidazolium triflate ([C 2 mim][CF 3 SO 3 ]) ionic liquid as extractant, in a hollow fibre membrane contactor. Due to the low distribution ratio of the thiol towards the ionic liquid, observed in single extraction, a regeneration step (stripping with vacuum or a sweep gas) was added to the extraction process, in order to maximize the concentration gradient overcoming thermodynamic constraints. The stripping with a sweep gas allowed for a complete regeneration of the ionic liquid producing a jet-fuel with sulphur content lower than 2 ppm. Since the controlling step of the process is the extraction of thiol from the Feed Phase to the ionic liquid Phase, the increase of the ionic liquid velocity and operating temperature may further enhance the process performance. The results obtained along with the ultra-low sulphur jet-fuel model produced prove the high potential of this integrated process as an alternative method for replacing the current expensive desulphurization process.

  • extraction and re extraction of phenylalanine by cationic reversed micelles in hollow fibre contactors
    Journal of Membrane Science, 1999
    Co-Authors: Margarida M Cardoso, R M C Viegas, Joao G Crespo
    Abstract:

    Abstract This work reports the extraction of phenylalanine with a reversed micellar system consisting of TOMAC/hexanol/n-heptane using hydrophobic hollow fibre modules. Extraction studies were performed under different hydrodynamic conditions and mass transfer correlations for the shell and tube sides were developed. The correlations were determined using a one-step calculation method and the results obtained are in agreement with the literature for the range of Reynolds numbers studied. Based on the obtained correlations and on the resistance in series model, a transport model was developed in which the phenylalanine concentration in the Feed Phase can be predicted during the experimental run. For the extraction process the model developed describes satisfactorily the evolution of phenylalanine concentration with time under different hydrodynamic conditions. The re-extraction process was found to be kinetically controlled due to the higher dynamic stability of reversed micelles when contacting a stripping Phase with high ionic strength. The experimental results obtained were described using a kinetic model developed. Simultaneous extraction/stripping of phenylalanine was also accomplished using two hollow fibre modules in series, using different volume Phase ratios. The mass transfer process was modelled and compared with the experimental results.