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A new nano-engineered hierarchical membrane for concurrent removal of surfactant and oil from oil-in-water nanoemulsion.

Qin D, Liu Z, Bai H, Sun DD, Song X - Sci Rep (2016)

Bottom Line: The physical and chemical properties of the overall membrane, including wettability, surface roughness, electric charge, thickness and structures, are delicately tailored through a nano-engineered fabrication process, that is, graphene oxide (GO) nanosheet assisted phase inversion coupled with surface functionalization.Compared with the membrane fabricated by conventional phase inversion, this novel membrane has four times higher water flux, significantly higher rejections of both oil (~99.9%) and surfactant (as high as 93.5%), and two thirds lower fouling ratio when treating surfactant stabilized oil-in-water nanoemulsion.Due to its excellent performances and facile fabrication process, this nano-engineered membrane is expected to have wide practical applications in the oil/water separation fields of environmental protection and water purification.

View Article: PubMed Central - PubMed

Affiliation: Energy Research Institute @ NTU, Interdisciplinary Graduate School, Nanyang Technological University, 639798, Singapore.

ABSTRACT
Surfactant stabilized oil-in-water nanoemulsions pose a severe threat to both the environment and human health. Recent development of membrane filtration technology has enabled efficient oil removal from oil/water nanoemulsion, however, the concurrent removal of surfactant and oil remains unsolved because the existing filtration membranes still suffer from low surfactant removal rate and serious surfactant-induced fouling issue. In this study, to realize the concurrent removal of surfactant and oil from nanoemulsion, a novel hierarchically-structured membrane is designed with a nanostructured selective layer on top of a microstructured support layer. The physical and chemical properties of the overall membrane, including wettability, surface roughness, electric charge, thickness and structures, are delicately tailored through a nano-engineered fabrication process, that is, graphene oxide (GO) nanosheet assisted phase inversion coupled with surface functionalization. Compared with the membrane fabricated by conventional phase inversion, this novel membrane has four times higher water flux, significantly higher rejections of both oil (~99.9%) and surfactant (as high as 93.5%), and two thirds lower fouling ratio when treating surfactant stabilized oil-in-water nanoemulsion. Due to its excellent performances and facile fabrication process, this nano-engineered membrane is expected to have wide practical applications in the oil/water separation fields of environmental protection and water purification.

No MeSH data available.


Related in: MedlinePlus

The pure water permeability and neutral solute selectivity of membrane.(a) The effect of GO weight fraction in nanocomposite dope solution on pure water permeability (PWP) of GO-P membrane. (b) The effect of hydrogel concentration on PWP and underwater oil contact angle of GO-P-S membrane. (c) Membrane PWP and selective layer pore radius (r1, MWCO, which is calculated from MWCO).
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f4: The pure water permeability and neutral solute selectivity of membrane.(a) The effect of GO weight fraction in nanocomposite dope solution on pure water permeability (PWP) of GO-P membrane. (b) The effect of hydrogel concentration on PWP and underwater oil contact angle of GO-P-S membrane. (c) Membrane PWP and selective layer pore radius (r1, MWCO, which is calculated from MWCO).

Mentions: The pure water permeability (PWP) of GO-P membrane can be tuned through controlling the weight fraction of GO sheet in nanocomposite dope solution. The PWP of GO-P membrane is enhanced significantly along with the increase of GO weight fraction from 0.3 wt% to 0.5 wt% while stabilized around 620 L m−2 h−1 bar−1 as GO weight fraction exceeding 0.5 wt% (Fig. 4a). In this study, GO-P membrane refers to GO weight fraction of 0.5 wt% in nanocomposite dope solution. Furthermore, delicate surface functionalization can be achieved through finely adjusting the concentration of hydrogel solution, with the positive correlation between underwater oil contact angle and hydrogel concentration revealed in Fig. 4b. Particularly, the increase of underwater oil contact angle becomes relatively insignificant as hydrogel concentration exceeding 200 mg/L. Therefore, the hydrogel concentration is optimized as 200 mg/L in order to balance surface wettability and membrane permeability.


A new nano-engineered hierarchical membrane for concurrent removal of surfactant and oil from oil-in-water nanoemulsion.

Qin D, Liu Z, Bai H, Sun DD, Song X - Sci Rep (2016)

The pure water permeability and neutral solute selectivity of membrane.(a) The effect of GO weight fraction in nanocomposite dope solution on pure water permeability (PWP) of GO-P membrane. (b) The effect of hydrogel concentration on PWP and underwater oil contact angle of GO-P-S membrane. (c) Membrane PWP and selective layer pore radius (r1, MWCO, which is calculated from MWCO).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4834549&req=5

f4: The pure water permeability and neutral solute selectivity of membrane.(a) The effect of GO weight fraction in nanocomposite dope solution on pure water permeability (PWP) of GO-P membrane. (b) The effect of hydrogel concentration on PWP and underwater oil contact angle of GO-P-S membrane. (c) Membrane PWP and selective layer pore radius (r1, MWCO, which is calculated from MWCO).
Mentions: The pure water permeability (PWP) of GO-P membrane can be tuned through controlling the weight fraction of GO sheet in nanocomposite dope solution. The PWP of GO-P membrane is enhanced significantly along with the increase of GO weight fraction from 0.3 wt% to 0.5 wt% while stabilized around 620 L m−2 h−1 bar−1 as GO weight fraction exceeding 0.5 wt% (Fig. 4a). In this study, GO-P membrane refers to GO weight fraction of 0.5 wt% in nanocomposite dope solution. Furthermore, delicate surface functionalization can be achieved through finely adjusting the concentration of hydrogel solution, with the positive correlation between underwater oil contact angle and hydrogel concentration revealed in Fig. 4b. Particularly, the increase of underwater oil contact angle becomes relatively insignificant as hydrogel concentration exceeding 200 mg/L. Therefore, the hydrogel concentration is optimized as 200 mg/L in order to balance surface wettability and membrane permeability.

Bottom Line: The physical and chemical properties of the overall membrane, including wettability, surface roughness, electric charge, thickness and structures, are delicately tailored through a nano-engineered fabrication process, that is, graphene oxide (GO) nanosheet assisted phase inversion coupled with surface functionalization.Compared with the membrane fabricated by conventional phase inversion, this novel membrane has four times higher water flux, significantly higher rejections of both oil (~99.9%) and surfactant (as high as 93.5%), and two thirds lower fouling ratio when treating surfactant stabilized oil-in-water nanoemulsion.Due to its excellent performances and facile fabrication process, this nano-engineered membrane is expected to have wide practical applications in the oil/water separation fields of environmental protection and water purification.

View Article: PubMed Central - PubMed

Affiliation: Energy Research Institute @ NTU, Interdisciplinary Graduate School, Nanyang Technological University, 639798, Singapore.

ABSTRACT
Surfactant stabilized oil-in-water nanoemulsions pose a severe threat to both the environment and human health. Recent development of membrane filtration technology has enabled efficient oil removal from oil/water nanoemulsion, however, the concurrent removal of surfactant and oil remains unsolved because the existing filtration membranes still suffer from low surfactant removal rate and serious surfactant-induced fouling issue. In this study, to realize the concurrent removal of surfactant and oil from nanoemulsion, a novel hierarchically-structured membrane is designed with a nanostructured selective layer on top of a microstructured support layer. The physical and chemical properties of the overall membrane, including wettability, surface roughness, electric charge, thickness and structures, are delicately tailored through a nano-engineered fabrication process, that is, graphene oxide (GO) nanosheet assisted phase inversion coupled with surface functionalization. Compared with the membrane fabricated by conventional phase inversion, this novel membrane has four times higher water flux, significantly higher rejections of both oil (~99.9%) and surfactant (as high as 93.5%), and two thirds lower fouling ratio when treating surfactant stabilized oil-in-water nanoemulsion. Due to its excellent performances and facile fabrication process, this nano-engineered membrane is expected to have wide practical applications in the oil/water separation fields of environmental protection and water purification.

No MeSH data available.


Related in: MedlinePlus