Mechanism responsible for flocculation in poly (n-isopropylacrylamide) temperature responsive dewatering-attractive interaction forces induced by surface hydrophobicity

G. Franks, E. Burdukova, H. Li, Naoyuki Ishida, J. P. O'Shea

Research output: Chapter in Book/Report/Conference proceedingConference contribution

6 Citations (Scopus)

Abstract

Temperature responsive polymers such as Poly (N-isopropylacrylamide) (PNIPAM) have been shown to have potential to improve water recovery from mineral tailings by using the polymer as a flocculant at temperature above the lower critical solution temperature (LCST 32°C) and then as a consolidation aid at temperature below the LCST. The mechanism for the flocculation (at high temperature) is shown to be hydrophobic and the mechanism for the repulsion (at low temperature) is shown to be steric repulsion. The contact angle between water and air on PNIPAM covered silica glass surfaces increases with increasing temperature and increases with increasing polymer molecular weight. Atomic force microscope (AFM) colloid probe surface force measurements at temperature below the LCST show steric repulsion which increases with polymer molecular weight. At temperature above the LCST, attraction is observed between the PNIPAM covered surfaces which increases as molecular weight of the polymer increases. The polar acid-base interfacial interaction forces have been estimated using contact angle measurements of three different liquids (water, formamide and diiodomethane) on PNIPAM coated silica glass surfaces. The results of these calculations are consistent with hydrophobic attraction at temperature above the LCST and steric repulsion at temperature below the LCST. Since the mechanism for the attraction is due to an increase in particle hydrophobicity it is also possible to use PNIPAM as a flotation collector for fine particles because it can produce hydrophobic floccs.

Original languageEnglish
Title of host publicationXXV International Mineral Processing Congress 2010, IMPC 2010
Pages4057-4067
Number of pages11
Volume5
Publication statusPublished - 2010
Externally publishedYes
Event25th International Mineral Processing Congress 2010, IMPC 2010 - Brisbane, QLD, Australia
Duration: Sep 6 2010Sep 10 2010

Other

Other25th International Mineral Processing Congress 2010, IMPC 2010
CountryAustralia
CityBrisbane, QLD
Period9/6/109/10/10

Fingerprint

Dewatering
Flocculation
hydrophobicity
Hydrophobicity
dewatering
flocculation
polymer
temperature
Temperature
Polymers
Molecular weight
Fused silica
silica
glass
Contact angle
Water
colloid
tailings
Force measurement
water

Keywords

  • Atomic force microscopy
  • Contact angle
  • Dewatering
  • Flocculation
  • Flotation
  • Hydrophobic attraction
  • Polar interfacial interactions
  • Solid-liquid separation
  • Temperature-sensitive polymer

ASJC Scopus subject areas

  • Earth-Surface Processes
  • Geology
  • Electrical and Electronic Engineering
  • Mechanical Engineering

Cite this

Franks, G., Burdukova, E., Li, H., Ishida, N., & O'Shea, J. P. (2010). Mechanism responsible for flocculation in poly (n-isopropylacrylamide) temperature responsive dewatering-attractive interaction forces induced by surface hydrophobicity. In XXV International Mineral Processing Congress 2010, IMPC 2010 (Vol. 5, pp. 4057-4067)

Mechanism responsible for flocculation in poly (n-isopropylacrylamide) temperature responsive dewatering-attractive interaction forces induced by surface hydrophobicity. / Franks, G.; Burdukova, E.; Li, H.; Ishida, Naoyuki; O'Shea, J. P.

XXV International Mineral Processing Congress 2010, IMPC 2010. Vol. 5 2010. p. 4057-4067.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Franks, G, Burdukova, E, Li, H, Ishida, N & O'Shea, JP 2010, Mechanism responsible for flocculation in poly (n-isopropylacrylamide) temperature responsive dewatering-attractive interaction forces induced by surface hydrophobicity. in XXV International Mineral Processing Congress 2010, IMPC 2010. vol. 5, pp. 4057-4067, 25th International Mineral Processing Congress 2010, IMPC 2010, Brisbane, QLD, Australia, 9/6/10.
Franks G, Burdukova E, Li H, Ishida N, O'Shea JP. Mechanism responsible for flocculation in poly (n-isopropylacrylamide) temperature responsive dewatering-attractive interaction forces induced by surface hydrophobicity. In XXV International Mineral Processing Congress 2010, IMPC 2010. Vol. 5. 2010. p. 4057-4067
Franks, G. ; Burdukova, E. ; Li, H. ; Ishida, Naoyuki ; O'Shea, J. P. / Mechanism responsible for flocculation in poly (n-isopropylacrylamide) temperature responsive dewatering-attractive interaction forces induced by surface hydrophobicity. XXV International Mineral Processing Congress 2010, IMPC 2010. Vol. 5 2010. pp. 4057-4067
@inproceedings{a8650a72c20a40b6a29b0a7d36d86645,
title = "Mechanism responsible for flocculation in poly (n-isopropylacrylamide) temperature responsive dewatering-attractive interaction forces induced by surface hydrophobicity",
abstract = "Temperature responsive polymers such as Poly (N-isopropylacrylamide) (PNIPAM) have been shown to have potential to improve water recovery from mineral tailings by using the polymer as a flocculant at temperature above the lower critical solution temperature (LCST 32°C) and then as a consolidation aid at temperature below the LCST. The mechanism for the flocculation (at high temperature) is shown to be hydrophobic and the mechanism for the repulsion (at low temperature) is shown to be steric repulsion. The contact angle between water and air on PNIPAM covered silica glass surfaces increases with increasing temperature and increases with increasing polymer molecular weight. Atomic force microscope (AFM) colloid probe surface force measurements at temperature below the LCST show steric repulsion which increases with polymer molecular weight. At temperature above the LCST, attraction is observed between the PNIPAM covered surfaces which increases as molecular weight of the polymer increases. The polar acid-base interfacial interaction forces have been estimated using contact angle measurements of three different liquids (water, formamide and diiodomethane) on PNIPAM coated silica glass surfaces. The results of these calculations are consistent with hydrophobic attraction at temperature above the LCST and steric repulsion at temperature below the LCST. Since the mechanism for the attraction is due to an increase in particle hydrophobicity it is also possible to use PNIPAM as a flotation collector for fine particles because it can produce hydrophobic floccs.",
keywords = "Atomic force microscopy, Contact angle, Dewatering, Flocculation, Flotation, Hydrophobic attraction, Polar interfacial interactions, Solid-liquid separation, Temperature-sensitive polymer",
author = "G. Franks and E. Burdukova and H. Li and Naoyuki Ishida and O'Shea, {J. P.}",
year = "2010",
language = "English",
isbn = "9781617820519",
volume = "5",
pages = "4057--4067",
booktitle = "XXV International Mineral Processing Congress 2010, IMPC 2010",

}

TY - GEN

T1 - Mechanism responsible for flocculation in poly (n-isopropylacrylamide) temperature responsive dewatering-attractive interaction forces induced by surface hydrophobicity

AU - Franks, G.

AU - Burdukova, E.

AU - Li, H.

AU - Ishida, Naoyuki

AU - O'Shea, J. P.

PY - 2010

Y1 - 2010

N2 - Temperature responsive polymers such as Poly (N-isopropylacrylamide) (PNIPAM) have been shown to have potential to improve water recovery from mineral tailings by using the polymer as a flocculant at temperature above the lower critical solution temperature (LCST 32°C) and then as a consolidation aid at temperature below the LCST. The mechanism for the flocculation (at high temperature) is shown to be hydrophobic and the mechanism for the repulsion (at low temperature) is shown to be steric repulsion. The contact angle between water and air on PNIPAM covered silica glass surfaces increases with increasing temperature and increases with increasing polymer molecular weight. Atomic force microscope (AFM) colloid probe surface force measurements at temperature below the LCST show steric repulsion which increases with polymer molecular weight. At temperature above the LCST, attraction is observed between the PNIPAM covered surfaces which increases as molecular weight of the polymer increases. The polar acid-base interfacial interaction forces have been estimated using contact angle measurements of three different liquids (water, formamide and diiodomethane) on PNIPAM coated silica glass surfaces. The results of these calculations are consistent with hydrophobic attraction at temperature above the LCST and steric repulsion at temperature below the LCST. Since the mechanism for the attraction is due to an increase in particle hydrophobicity it is also possible to use PNIPAM as a flotation collector for fine particles because it can produce hydrophobic floccs.

AB - Temperature responsive polymers such as Poly (N-isopropylacrylamide) (PNIPAM) have been shown to have potential to improve water recovery from mineral tailings by using the polymer as a flocculant at temperature above the lower critical solution temperature (LCST 32°C) and then as a consolidation aid at temperature below the LCST. The mechanism for the flocculation (at high temperature) is shown to be hydrophobic and the mechanism for the repulsion (at low temperature) is shown to be steric repulsion. The contact angle between water and air on PNIPAM covered silica glass surfaces increases with increasing temperature and increases with increasing polymer molecular weight. Atomic force microscope (AFM) colloid probe surface force measurements at temperature below the LCST show steric repulsion which increases with polymer molecular weight. At temperature above the LCST, attraction is observed between the PNIPAM covered surfaces which increases as molecular weight of the polymer increases. The polar acid-base interfacial interaction forces have been estimated using contact angle measurements of three different liquids (water, formamide and diiodomethane) on PNIPAM coated silica glass surfaces. The results of these calculations are consistent with hydrophobic attraction at temperature above the LCST and steric repulsion at temperature below the LCST. Since the mechanism for the attraction is due to an increase in particle hydrophobicity it is also possible to use PNIPAM as a flotation collector for fine particles because it can produce hydrophobic floccs.

KW - Atomic force microscopy

KW - Contact angle

KW - Dewatering

KW - Flocculation

KW - Flotation

KW - Hydrophobic attraction

KW - Polar interfacial interactions

KW - Solid-liquid separation

KW - Temperature-sensitive polymer

UR - http://www.scopus.com/inward/record.url?scp=84877910290&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84877910290&partnerID=8YFLogxK

M3 - Conference contribution

SN - 9781617820519

VL - 5

SP - 4057

EP - 4067

BT - XXV International Mineral Processing Congress 2010, IMPC 2010

ER -