Effect of non-solvent additives on the structure and performance of PVDF hollow fiber membrane contactor for CO2 stripping

Naim, R.; Ismail, Ahmad Fauzi; Mansourizadeh, Amir

doi:10.1016/j.memsci.2012.08.052

Cited by 68 publications

(36 citation statements)

References 48 publications

(66 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results can be attributed to the changes in the membrane structures. Finger-like voids are commonly related to the weak mechanical strength which is not usually desired for polymer and ceramic hollow fiber membranes [66]. As discussed in Section 3.2, the proportion of the finger-like structure decreases and the sponge-like structure increases with the increases in the LiCl, acetone, and PVP contents of the dope solutions.…”

Section: Effect Of the Additives On The Membrane Surface Propertiesmentioning

confidence: 99%

Effect of non-solvent additives on the morphology and separation performance of poly( m -phenylene isophthalamide) (PMIA) hollow fiber nanofiltration membrane

Wang

Zhao

et al. 2015

Desalination

View full text Add to dashboard Cite

• PMIA hollow fiber NF membranes were fabricated.• Effects of non-solvent additives on the morphology and separation performance were studied.• High content of non-solvent additives resulted in narrow pore size, pore size distribution and high rejection. Newly designed poly(m-phenylene isophthalamide) (PMIA) hollow fiber nanofiltration membranes were fabricated containing non-solvent additives, i.e., lithium chloride (LiCl), acetone and PVP by dry-jet wet spinning technology. The effects of non-solvent additives on the morphology and separation performance were investigated. The addition of non-solvent additives in the dopes enhanced the viscosity significantly. The membrane crosssections were monitored by scanning electron microscopy (SEM). The results indicated that by increasing the concentration of non-solvent additives, the morphologies changed from finger-like to sponge-like, and the outer skin-layer thickness was slightly increased. The rejections to various salts and pure water permeability (PWP) of these membranes were determined. The mean pore size and molecular weight cut-off (MWCO) were estimated using the solute rejection method. The results showed that the salt rejection of the membranes decreased in the order of R(Na 2 SO 4 ) N R(MgSO 4 ) N R(NaCl) N R(MgCl 2 ), and as the concentrations of non-solvent additives increased, the PWPs, mean pore sizes and MWCOs of the PMIA membranes all decreased. The atomic force microscope (AFM) experiments demonstrated that a smooth membrane surface was formed by adding non-solvent additives. Furthermore, the stress values at break, the elongation at break and the elastic modulus of the fibers increased as non-solvent additive contents increased. a b s t r a c t a r t i c l e i n f o

show abstract

Section: Effect Of the Additives On The Membrane Surface Propertiesmentioning

confidence: 99%

Effect of non-solvent additives on the morphology and separation performance of poly( m -phenylene isophthalamide) (PMIA) hollow fiber nanofiltration membrane

Wang

Zhao

et al. 2015

Desalination

View full text Add to dashboard Cite

show abstract

“…The membrane was designed to improve the water vapor flux by introducing the combination of a narrow finger-like structure with a thicker layer of sponge-like pore network. It is well known that a narrow finger-like structure is desirable to reduce the mass resistance during vapor transport and the sponge-like structure will strengthen the membrane matrix from easily collapsing during a long operation [27,28]. Therefore, to prepare a porous membrane with small pore size and narrow finger-like structure, which are favorable parameters for the MD process, EG was introduced into the spinning dope as a phase-inversion promoter additive.…”

Section: Dcmd Experimentsmentioning

confidence: 99%

Dye wastewater treatment by direct contact membrane distillation using polyvinylidene fluoride hollow fiber membranes

Mokhtar

Lau

Ismail

2014

Journal of Polymer Engineering

View full text Add to dashboard Cite

The potential of 18 wt.% polyvinylidene fluoride (PVDF) hollow fiber membrane blended with ethylene glycol (EG) for the treatment of dye solution using direct contact membrane distillation (DCMD) system was investigated. The PVDF membrane was prepared using the dryjet wet spinning method and was characterized in terms of membrane morphology, porosity, wetting pressure, gas permeability and degree of hydrophobicity. The membrane was tested using dye solution containing 0.5 g l -1 reactive black 5 (RB5). The experimental period was prolonged to 6 h in order to analyze the fouling tendency and membrane durability during the DCMD process. The results showed that the modified PVDF membrane was able to produce consistent flux (i.e., 9.82 ± 0.52 kg m -2 h -1 ) throughout the DCMD experiment while maintaining excellent dye rejection (i.e., 99.86 ± 0.04%). With respect to membrane fouling, it was found that the lumen side of the membrane was significantly stained with color (compared to outer membrane surface) due to the physical-chemical interaction between reactive dye and membrane structure. Although membrane fouling was experienced in this study, its impact on MD performance in terms of flux and rejection was negligible, mainly because MD is not a pressure-driven process.

show abstract

“…Meanwhile, mixed additives have been a recent trend for polymer membrane preparation due to the synergistic effect among different additives. Polyethylene glycol (PEG) is a commonly used pore-former for membrane preparation, and the PVDF membrane prepared with PEG normally possesses a macrovoid structure with high porosity owing to the instantaneous phase inversion process induced by PEG [29][30][31][32][33]. LiCl is another frequently-used additive, which tends to enhance the viscosity of the casting solution.…”

Section: Introductionmentioning

confidence: 99%

Preparation of PVDF-CTFE hydrophobic membranes for MD application: Effect of LiCl-based mixed additives

Zheng

Wei

et al. 2016

Journal of Membrane Science

View full text Add to dashboard Cite

a b s t r a c tHydrophobic flat-sheet membranes were prepared by poly (vinylidene fluoride-co-chlorotrifluoroethylene) (PVDF-CTFE) via the non-solvent induced phase separation (NIPS) process for membrane distillation (MD) application. Different types of LiCl-based mixed additives were applied to investigate their effects on membrane properties and MD performance. The membranes were evaluated in terms of membrane morphology, pore size and distribution, porosity, surface roughness, hydrophobicity, as well as the direct contact membrane distillation (DCMD) performance. Clear evidences were obtained that the mixed additives altered the phase inversion process, which resulted in the variation in membrane morphology, structure, properties and performance. The mass ratio of PEG/LiCl ranging from 5:0 to 0:5 was comprehensively investigated to study the synergistic effects of two additives on PVDF-CTFE membranes. The membrane M5 (PEG:LiCl ¼1:1, total content 8 wt% ) showed optimal properties and MD performance for combining the structure of higher hydrophobicity and pore interconnectivity, small pore size and narrow pore size distribution. The addition of LiCl to PEG-containing solutions benefited the solid-liquid demixing process, which increased the hydrophobicity, porosity, pore interconnectivity, and MD performance of the resultant membranes. While added PEG to LiCl-containing solutions showed slightly influences. Furthermore, it was also found that PVP/LiCl and glycerol/LiCl were not suitable for hydrophobic membrane preparation as they strikingly reduced membrane hydrophobicity. While H 3 PO 4 and H 2 O were confirmed suitable to mix with LiCl for hydrophobic PVDF-CTFE membrane preparation.

show abstract

Effect of non-solvent additives on the structure and performance of PVDF hollow fiber membrane contactor for CO2 stripping

Cited by 68 publications

References 48 publications

Effect of non-solvent additives on the morphology and separation performance of poly( m -phenylene isophthalamide) (PMIA) hollow fiber nanofiltration membrane

Effect of non-solvent additives on the morphology and separation performance of poly( m -phenylene isophthalamide) (PMIA) hollow fiber nanofiltration membrane

Dye wastewater treatment by direct contact membrane distillation using polyvinylidene fluoride hollow fiber membranes

Preparation of PVDF-CTFE hydrophobic membranes for MD application: Effect of LiCl-based mixed additives

Contact Info

Product

Resources

About