Surface force measurements of polyelectrolyte mediated interactions:

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Surface force measurements of polyelectrolyte
mediated interactions Implications on tailings
paste technology Thomas Abraham NSERC
Industrial Research Chair in Oil Sands
Engineering Department of Chemical and Materials
Engineering University of Alberta Edmonton Alberta
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• Profile
• Importance of Study
• Polyelectrolyte- assisted flocculation
• (Paste Technology)
• Objectives
• Materials Method
• Results
• Conclusions

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Importance of Study
Process technology for Disposal of fine tails
Syncrude data
Cumulative fine tails
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Polyelectrolyte- assisted flocculation
Paste technology
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Polyelectrolyte- particle interaction
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Floc- structure
Loose flocs
Dense flocs
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Objectives
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Materials
Rgf (pH, CS )
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Interferometric Surface Forces Apparatus
Surface Forces versus Distance
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Results Forces between mica surfaces
3mM MgCl2/ PAA/ pH 8
50 ppm
10 ppm
j
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Results Forces between mica surfaces
3mM CaCl2/ 10 ppm PAA/ pH 8
J
J
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Conclusions

• PAA mediated surface interactions are strong
  function of

(a) divalent ion size
(b) Polyelectrolyte/ divalent ion concentration
ratio
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Conclusions (Continued)

• Presence or use of these counterions in systems
  containing PAA can have profound effects on
  relevant surface interactions

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Further work

• Effects of
• charge density molecular
• weight of polyelectrolyte
• divalent salt concentration
• other constituents such as surfactants

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Acknowledgments
Professor Zhenghe Xu Professor Jacob Masliyah
Atte Kumplainen RIT YKI, Stockholm NSERC
Industrial Oil sand Chair