Inverted polarity micellar enhanced ultrafiltration for the treatment of heavy metal polluted wastewater

Nick Hankins, Nidal Hilal, Oluwaseun O. Ogunbiyi, Barry Azzopardi

    Research output: Contribution to journalArticle

    Abstract

    Membrane separation technologies are being applied with increasing frequency in the treatment of industrial and municipal wastewater, as a means of coping with increasingly stringent environmental regulations regarding waste-water discharge. In particular, the research work presented here is driven by the need to reduce the amount of heavy metals released into aquatic environments. Micellar enhanced ultrafiltration (MEUF) is a colloidal-based waste-water treatment process. The adsorptive capacity of the Stern layer of a large, anionic surfactant micelle is used to capture heavy metals ions; the micelles are, in turn, trapped behind a polymeric ultrafiltration membrane. Experimental work has investigated the possibility of increasing the capture of pollutant ions, by collapsing the Stern and diffuse layer radii within the hydrodynamic diameter of micelles of sodium dodecyl sulphate. This involves bringing the micelles to a state of near-flocculation through the addition of multivalent ions; these ions include aluminium, which is deliberately added as a flocculant ion, and the target heavy metal ions in solution, which are represented here by zinc. The near flocculation is achieved through the combination of surfactant, aluminium and zinc ion concen trations. The electrical triple-layer compression and near-flocculation of the micelle means that a greater fraction of the metal ions present in solution are dragged along with the micelle. The high porosity and permeability of the near-flocculated (or fully flocculated) micelles also reduces the tendency for gel formation, and thus fouling, on the ultrafiltration membrane surface. A combination of titration analysis and ultrafiltration experiments has investigated the relationship between the half-lives of permeate flux decline and the micelle-zinc binding ratios. This has allowed us to determine conditions which allow an optimum separation efficiency. Overall, the experiments have demonstrated a potential for improving the efficiency of the treatment of wastewater containing heavy metal ions.

    Original languageEnglish (US)
    Pages (from-to)185-202
    Number of pages18
    JournalDesalination
    Volume185
    Issue number1-3
    DOIs
    StatePublished - May 22 2005

    Fingerprint

    Micelles
    Ultrafiltration
    Heavy Metals
    ultrafiltration
    Heavy metals
    Wastewater
    heavy metal
    wastewater
    ion
    Metal ions
    Ions
    Flocculation
    Heavy ions
    flocculation
    Zinc
    zinc
    Aluminum
    Membranes
    membrane
    surfactant

    Keywords

    • Heavy metal
    • Inverted polarity
    • Ultrafiltration
    • Waste water

    ASJC Scopus subject areas

    • Chemistry(all)
    • Chemical Engineering(all)
    • Materials Science(all)
    • Water Science and Technology
    • Mechanical Engineering

    Cite this

    Inverted polarity micellar enhanced ultrafiltration for the treatment of heavy metal polluted wastewater. / Hankins, Nick; Hilal, Nidal; Ogunbiyi, Oluwaseun O.; Azzopardi, Barry.

    In: Desalination, Vol. 185, No. 1-3, 22.05.2005, p. 185-202.

    Research output: Contribution to journalArticle

    Hankins, Nick ; Hilal, Nidal ; Ogunbiyi, Oluwaseun O. ; Azzopardi, Barry. / Inverted polarity micellar enhanced ultrafiltration for the treatment of heavy metal polluted wastewater. In: Desalination. 2005 ; Vol. 185, No. 1-3. pp. 185-202.
    @article{0e3dfd4d71204aac97ef096e739c533f,
    title = "Inverted polarity micellar enhanced ultrafiltration for the treatment of heavy metal polluted wastewater",
    abstract = "Membrane separation technologies are being applied with increasing frequency in the treatment of industrial and municipal wastewater, as a means of coping with increasingly stringent environmental regulations regarding waste-water discharge. In particular, the research work presented here is driven by the need to reduce the amount of heavy metals released into aquatic environments. Micellar enhanced ultrafiltration (MEUF) is a colloidal-based waste-water treatment process. The adsorptive capacity of the Stern layer of a large, anionic surfactant micelle is used to capture heavy metals ions; the micelles are, in turn, trapped behind a polymeric ultrafiltration membrane. Experimental work has investigated the possibility of increasing the capture of pollutant ions, by collapsing the Stern and diffuse layer radii within the hydrodynamic diameter of micelles of sodium dodecyl sulphate. This involves bringing the micelles to a state of near-flocculation through the addition of multivalent ions; these ions include aluminium, which is deliberately added as a flocculant ion, and the target heavy metal ions in solution, which are represented here by zinc. The near flocculation is achieved through the combination of surfactant, aluminium and zinc ion concen trations. The electrical triple-layer compression and near-flocculation of the micelle means that a greater fraction of the metal ions present in solution are dragged along with the micelle. The high porosity and permeability of the near-flocculated (or fully flocculated) micelles also reduces the tendency for gel formation, and thus fouling, on the ultrafiltration membrane surface. A combination of titration analysis and ultrafiltration experiments has investigated the relationship between the half-lives of permeate flux decline and the micelle-zinc binding ratios. This has allowed us to determine conditions which allow an optimum separation efficiency. Overall, the experiments have demonstrated a potential for improving the efficiency of the treatment of wastewater containing heavy metal ions.",
    keywords = "Heavy metal, Inverted polarity, Ultrafiltration, Waste water",
    author = "Nick Hankins and Nidal Hilal and Ogunbiyi, {Oluwaseun O.} and Barry Azzopardi",
    year = "2005",
    month = "5",
    day = "22",
    doi = "10.1016/j.desal.2005.02.077",
    language = "English (US)",
    volume = "185",
    pages = "185--202",
    journal = "Desalination",
    issn = "0011-9164",
    publisher = "Elsevier",
    number = "1-3",

    }

    TY - JOUR

    T1 - Inverted polarity micellar enhanced ultrafiltration for the treatment of heavy metal polluted wastewater

    AU - Hankins, Nick

    AU - Hilal, Nidal

    AU - Ogunbiyi, Oluwaseun O.

    AU - Azzopardi, Barry

    PY - 2005/5/22

    Y1 - 2005/5/22

    N2 - Membrane separation technologies are being applied with increasing frequency in the treatment of industrial and municipal wastewater, as a means of coping with increasingly stringent environmental regulations regarding waste-water discharge. In particular, the research work presented here is driven by the need to reduce the amount of heavy metals released into aquatic environments. Micellar enhanced ultrafiltration (MEUF) is a colloidal-based waste-water treatment process. The adsorptive capacity of the Stern layer of a large, anionic surfactant micelle is used to capture heavy metals ions; the micelles are, in turn, trapped behind a polymeric ultrafiltration membrane. Experimental work has investigated the possibility of increasing the capture of pollutant ions, by collapsing the Stern and diffuse layer radii within the hydrodynamic diameter of micelles of sodium dodecyl sulphate. This involves bringing the micelles to a state of near-flocculation through the addition of multivalent ions; these ions include aluminium, which is deliberately added as a flocculant ion, and the target heavy metal ions in solution, which are represented here by zinc. The near flocculation is achieved through the combination of surfactant, aluminium and zinc ion concen trations. The electrical triple-layer compression and near-flocculation of the micelle means that a greater fraction of the metal ions present in solution are dragged along with the micelle. The high porosity and permeability of the near-flocculated (or fully flocculated) micelles also reduces the tendency for gel formation, and thus fouling, on the ultrafiltration membrane surface. A combination of titration analysis and ultrafiltration experiments has investigated the relationship between the half-lives of permeate flux decline and the micelle-zinc binding ratios. This has allowed us to determine conditions which allow an optimum separation efficiency. Overall, the experiments have demonstrated a potential for improving the efficiency of the treatment of wastewater containing heavy metal ions.

    AB - Membrane separation technologies are being applied with increasing frequency in the treatment of industrial and municipal wastewater, as a means of coping with increasingly stringent environmental regulations regarding waste-water discharge. In particular, the research work presented here is driven by the need to reduce the amount of heavy metals released into aquatic environments. Micellar enhanced ultrafiltration (MEUF) is a colloidal-based waste-water treatment process. The adsorptive capacity of the Stern layer of a large, anionic surfactant micelle is used to capture heavy metals ions; the micelles are, in turn, trapped behind a polymeric ultrafiltration membrane. Experimental work has investigated the possibility of increasing the capture of pollutant ions, by collapsing the Stern and diffuse layer radii within the hydrodynamic diameter of micelles of sodium dodecyl sulphate. This involves bringing the micelles to a state of near-flocculation through the addition of multivalent ions; these ions include aluminium, which is deliberately added as a flocculant ion, and the target heavy metal ions in solution, which are represented here by zinc. The near flocculation is achieved through the combination of surfactant, aluminium and zinc ion concen trations. The electrical triple-layer compression and near-flocculation of the micelle means that a greater fraction of the metal ions present in solution are dragged along with the micelle. The high porosity and permeability of the near-flocculated (or fully flocculated) micelles also reduces the tendency for gel formation, and thus fouling, on the ultrafiltration membrane surface. A combination of titration analysis and ultrafiltration experiments has investigated the relationship between the half-lives of permeate flux decline and the micelle-zinc binding ratios. This has allowed us to determine conditions which allow an optimum separation efficiency. Overall, the experiments have demonstrated a potential for improving the efficiency of the treatment of wastewater containing heavy metal ions.

    KW - Heavy metal

    KW - Inverted polarity

    KW - Ultrafiltration

    KW - Waste water

    UR - http://www.scopus.com/inward/record.url?scp=29144442846&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=29144442846&partnerID=8YFLogxK

    U2 - 10.1016/j.desal.2005.02.077

    DO - 10.1016/j.desal.2005.02.077

    M3 - Article

    VL - 185

    SP - 185

    EP - 202

    JO - Desalination

    JF - Desalination

    SN - 0011-9164

    IS - 1-3

    ER -