Charles Q' Jia

1
Petcoke-Derived Activated Carbons for
Environmental Applications

• Charles Q. Jia
• University of Toronto
• _at_ University of Calgary Petcoke Utilization
  Workshop

2
Outline

• Oil-sand Fluid Coke
• Activated Carbon
• Activation processes
• Characteristics
• Applications
• Water purification
• Air purification Hg vapour capture
• Electric energy storage electrochemical super
  capacitor

3
Oil-sand fluid coke

• Production 10,000 t/day
• Compositions
• Volatile content 5
• Ash content (V, Fe, Si ) 5,
• High sulphur 7
• Low reactivity onion-like structure SSA 8
  m2/g
• Particle size 0.1 0.2 mm in diameter

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Activated Carbon

• High specific surface area SSA gt 200 m2/g
• Common raw materials coal, wood, coconut shell
• Chemical (e.g. KOH) and physical (e.g CO2 and
  H2O) activation
• Other chemicals (e.g. sulphur) added for
  functionality
• C SO2 ? CO2 ½ S2
• Fluid coke as a raw material
• already carbonized ? high yield
• high sulphur content ? sulphur-impregnated
  activated carbon

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Activation Processes and Activated Carbons
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Fluid coke-derived Activated Carbon
Before activation
(SSA 8 m2/g)
After activation
(SSA 2500 m2/g)
7
Markets for Activated Carbon

• World
• 1.1 x 109 /y
• growth 5/y to 2010
• Current uses
• 1 MT/y
• air purification
• water purification
• Future uses
• Hg vapour (2000 T/y) capture 20 200 MT/y
• Electric energy storage devices super-capacitor
  (capacitor bank, 1 kg per car?)

8
Air Purification

• High surface area provides adsorption sites for
  air contaminants
• AC as universal adsorbent
• Odour control
• Hg capture
• Surface can be modified chemically SIAC for Hg

9
Hg Adsorption Capacities at 125oC
VAC SAC FC-1
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Water Purification

• Inorganic contaminants removal
• Metal cations (e.g. Hg, Pb, Cd, Cr)
• Anions (e.g. Cl-,Br-)
• Organic contaminants removal
• Dissolved organics (e.g. PAHs) in the produced
  water in the petroleum industry (one of the
  topics of the U of T and U of C collaboration)
• Colour removal from the industrial waste water
  (e.g. pulping waste water)

11
Electric Energy Storage Using Super-capacitor

• Like batteries, capacitors are electric energy
  storage devices.
• Regular batteries have higher energy density than
  regular capacitors.
• Regular capacitors have higher power density than
  regular batteries.
• Super/ultra capacitors have both high power and
  energy densities.

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Applications
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Ideal Activated Carbon for Super-Capacitors

• High surface area (1000 to 3000 m2/g)
• Tailored pore structure
• Good electrical conductivity
• High purity
• Relatively low cost
• High capacitance gt 150 F/g
• (200 F/g has been achieved with the fluid
  coke-derived AC)

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Challenges and Opportunities

• Although it is feasible to remove sulphur in the
  petcoke, a better strategy is needed for sulphur
  management.
• There is a need to better understand the behavior
  of metals (e.g. V) during activation and develop
  technologies for recovering valuable metals.
• Activated carbon is much more reactive than the
  petcoke. There seems an opportunity to gasify
  the spent activated carbon.
• There is a need to develop technologies for
  recycling and reuse of activating agent.
• There is a need to better understand the
  processes that control the pore size distribution.

15
Acknowledgements

• Natural Sciences and Engineering Research
  Council of Canada
• Alberta Energy Research Institute
• Syncrude Canada Ltd
• Hudson Bay Mining and Smelting