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Nanomaterialer – viktig for gode framtidige løsninger for energi og miljø
Professor Magnus RønningInstitutt for kjemisk prosessteknologi,
Norges teknisk-naturvitenskapelige universitet, NTNUTrondheim
Nanotechnology applications NTNU
Fuelcells
Solarcells
Batteries/ energy storage
Green Energy
Hydrogen
Better air quality
Water treatment
Environment
CO2capture
Health
Diagnostics
Drug delivery
Lab-on-a-chip
Tissueon a chip
ICTData storage
Novel semiconductor
devices
Sensors
Oil production
Nanomechanics
Oil Gas Minerals
Toolboxes available at NTNUTheory/
modellingCharacterisation/
ValidationSynthesis/
Nanostructuring
New Materialsand
Technologies
NTNU NanoLab• Research
3 scientific areas:- Bionanotechnology- Nano-component technology - Nanotechnology for green energy systems
• Infrastructure NanoLab Cleanroom
- Investment 200 MNOK- Operating budget about 20 MNOK/year
Several other nano-related laboratory facilities
• EducationMSc. Study program in Nanotechnology
© 2006 Bruno & Lígia Rodrigues.
Challenge 1: Greenhouse gases - CO2 capture in power plants and process industry
Membranes for CO2 capture: in post combustion –in precombustion – in oxyfuel combustion –environmental friendly processes – no chemicals needed
New membrane materials investigated on nanoscale1. Hybrid materials / NanocompositesThe membrane can be tailored using nanoparticles to increase the separation of gas components
PMP with 25% TiO2 Self-organised PVAc with ZA4
2. Carbon Molecular Sieve MembranesPores are tailored in the range less than 1 nm– from Hollow Polymeric Fibres to CMS membranes by controlled pyrolysis
3. Facilitated Transport Membranes withNanoscale carriers in the material
Enzymes are mobile carriers (For CO2 capture we learn from nature – breathing)
The enzyme carbonic anhydrase (CA) helps to transport CO2 as HCO3
-
The NTNU Fixed Site Carrier (FSC) membrane is mimicking nature
H2O in the flue gas helpsto convert the CO2 to HCO3
- in the PVAmMembrane, hence CO2
capture is very efficient
May-Britt Hägg, NTNU
From NANO in lab to DEMO at site -minimum ~15 years – research takes time
Carbon Molecular Sieve MembranesRenewable Energy: In 2008 a NTNU spin-off company, MemfoACT, was established based on this patented technology,
• Producing membranes for upgrading of biogas to high quality fuels
• The company has now a demonstration pilot at GLØR biogas plant, Lillehammer
CO2 capture with FSC membrane Developed at NTNU – demonstrated on small pilot scale at a coal fired power plant in Portugal 2011Currently setting up a project team with international partners for scaling up the membrane towards demo
At EDP’s power plant In Sines, Portugal
May-Britt Hägg, NTNU
Challenge 2: Renewable energy:-Preparing membranes for saline power production
SEM images of membranes with the different linking monomers
Trimesoyl chlorideSuccinyl chloride Malonyl chloride
The membrane must be very thin(a few nanometres) in order to achievehigh power density
Key components: Pressure exchanger and membrane
Key components: Pressure exchanger and membrane
Global potential: 1600‐1700 TWh/annually
Global potential: 1600‐1700 TWh/annually
May-Britt Hägg, NTNU
Challenge 3: Air pollution – NOx and NH3-Commitment through the Gothenberg Protocol
Problem:
Nitrogen oxides (NOx) are still a severe environmental problem despite decades of global focus
Norwegian NOx emissions for 2011 was 14% higher than the Norwegian obligation in the Gothenberg Protocol
Main sources of NOx
• Any process involving nitrogen and oxygen at high temperature
• Combustion (also internal combustion engines)
• Nitric acid production
• Pyrometallurgy
Harmful effects of NOx
• It is a lung irritant and may aggravate lung disease
• It contributes to acid rain and photochemical smog
• It may react with organic compounds in the atmosphere to form ground-level ozone
www.klif.no:
How can we fulfil our obligations?
Solution:
It is evident that an increased effort involving novel approaches are necessary in order to achieve a technology breakthrough:
Nanoscale control of all stages in the process:
• Selective catalytic reduction (SCR)
• Wet scrubbing
• Separation and direct decomposition
Opportunities:
Local Norwegian advantage:
Yara international ASA is a world leading company in the the field of Nitrogen and NOx chemistry and the largest producer of fertilizer in the world.
A large offshore and shipping industry with an interest in meeting the increasingly strict legislations.
High-profile research groups with decades of experience in NOx chemistry and catalysis at SINTEF, UiO, TUC and NTNU
Selective catalytic reduction (SCR) is the state of the art in NOx removal from heavy engine exhaust, in which NOx is reduced by ammonia (often generated in situ from urea).
Magnus Rønning, Edd A. Blekkan, NTNU
Well-defined nanoparticles:Composition, size, stability
SCR: Ordered mesoporous alumina with controlled pore structure and acidity:
Challenge 4: Utilisation of our natural gas resources -Natural gas conversion
Opportunities:
• Large natural gas reserves:
• At present: The gas is exported as natural gas
• New scenario: Shale-gas gives low gas prices
• Solution: Upgrading and refining to value-added products:
• Synthetic fuels and chemicals (gas to liquids)• Commercial interest from Norwegian industry• Technology can also be applied to biomass (BTL)
http://www.regjeringen.no
http://www.creditwritedowns.com
Will Norway be an important supplier of oil and natural gas also in the next decades?
Natural gas valorisation: -Liquid fuels productionGas to liquids (GTL):
• A chemical process converting natural gas to hydrocarbons using Fischer-Tropsch synthesis
• Several large-scale commercial plants world-wide, such as the Shell PEARL facility in Qatar (below)
• The PEARL GTL plant produces 140,000 barrels of GTL products per day
• The Fischer-Tropsch synthesis is carried out using cobalt nanoparticles as catalyst
• The Fischer-Tropsch reactor in the PEARL plant contains 1025 cobalt nanoparticles
http://www.shell.com
13 Magnus Rønning, ICEC 2012
The Fischer-Tropsch synthesis
H C Co AlO
H2:CO:CO2
Natural Gas
Synthesis gas production
Fischer-Tropsch Synthesis
Product upgrade (Hydrogenation - Hydrocracking)
SteamOxygen
/ steam
-CH2-
15-25%
65-85%
0-30%
FT-DieselConventional
Diesel
27
Co58.93
• Reaction mechanism? • Structure sensitivity?• Active phase?• Main deactivation mechanism?
Complexity
Magnus Rønning, Anders Holmen, John Walmsley, NTNU, Statoil, SINTEF
14 Magnus Rønning, ICEC 2012
Catalyst deactivation in Fischer-Tropsch synthesis
Re-oxidation
Carbidisation
Carbon formation
Co-support mixed compounds
Attrition
Surface reconstruction
Phase transformation
Poisoning
Sintering
H O C Co Al S
Cobalt crystallites
Support
Amorphous
Sulphur
Nitrogen
Crystalline
N.E. Tsakoumis, M. Rønning, Ø. Borg, E. Rytter, A. Holmen, Deactivation of cobalt based Fischer-Tropsch catalysts: A review, Catal. Today, 154 (2010), 162-182
TOS
Catalyst activity (a.u.) Initial
deactivation
Long term deactivation
Magnus Rønning, Anders Holmen, NTNU, Statoil, SINTEF
Advanced characterisation at industrially relevant reaction conditions
The formation of divalent tetrahedrallycoordinated cobalt observed duringreaction using synchrotron radiation
N.E. Tsakoumis, A. Voronov, M. Rønning, W. van Beek, Ø. Borg, E. Rytter, A. Holmen, J. Catal. 291 (2012) 138–148
@ 18bar, 220oC, >61% CO conv. (32 h)
XAS
XRD
Raman
MS
European Synchrotron Radiation Facility (ESRF), France
Quartz capillary reactor:1 mm in ø, 20 μm wall thickness
Adsorption of CO on Co(1120) as observed by Scanning Tunnelling Microscopy (STM): Atomic resolution
Hilde Venvik, Anne Borg NTNU
Adsorption of CO on Co(11-20) as observed by Scanning Tunnelling Microscopy (STM):
• CO makes the Co atoms at the step edges mobile!
• The surface becomes reconstructed
Hilde J. Venvik, Cecilie Berg and Anne Borg: Surface Science 397 (1998) 322
3.8 nm
Clean Co(11-20) surfacewith Co atoms visible
Reconstructed Co(11-20) surface with CO adsorbed
(1x1) unit cell
Sequence of 100 nm x 100 nm STM images with increasing CO exposure @ ~2x10-9 mbar: • CO saturation, surface fully covered by
trough-and-ridge structure. • Well-ordered regions display (3 x 1) periodicity
http://www.wired.com
Challenge 5: Energy storage-Li-ion batteries
Problem:
• Current Li-based battery technology is not sufficiently stable and safe
• High-energy chemistry involved
• The short-term fix is the old Ni-Cd batteries…
• How can we improve the current technology?
Challenge 5: Energy storage-High energy and power density
Energy & Environmental Science, 2010, 3(2)
MnOx based Li-ion batteries• Environmentally friendly and safe
• Low price and abundant
• Properties:
• Capacity: 1232/308 mAh g-1
• Voltage: 0.4/3 V vs Li+/Li
Problems:
• Poor cyclic stability
• Poor rate capability
MnO6 Octahedron
Morphology and microstructures of aligned carbon nanotubes and ACNT@MnO2
ACNT MnO2_6h
Voltage profiles and stability
De Chen, Fride Vullum-Bruer, NTNU
Methanol fuel cells (alternative to battery?)• High energy density
• Easy methanol handling using already available petrol distribution network
• Pt and Pt alloy are typical anode catalysts
Drawbacks
• Expensive
• Slow anode kinetics (CO poisoning)
• Methanol cross-over
Improvement of CO tolerance eHCO Ru Pt OH-Ru CO-Pt 2
Lowering the Pt-CO bond strength or enhance the reactivity of adsorbed CO ?
The ligand effect (the electronic effect)
Challenge 6: Energy conversion-Replace the internal combustion engine by 2050?
Strategy of improving the dispersion of Ptnanoparticles on carbon nanofibres (CNF)
Catalysts preparation (Ex-situ polyol method)Deposition of pre-synthesized Pt colloids on carbon materials with different surface oxygen groups
Refluxed at 145o Cin N2 atm for 3 hr
Dark color
H2PtCl6 solution in EG + 0.5M NaOH
(pH 12)Golden Yellow color
XC72 (1.6 % O cont)
XC72_N (5.5 % O cont)
CNF_N(6 % O cont)
CNF_N_1K(1.8 % O cont)
Pt-XC72 Pt-XC72_N Pt-CNF_N Pt-CNF_N_1K
Pt0 colloidal solution
TEM images of Pt NCs in colloidal and on various
carbon supports with the Ptwt % in the range 16-18%
Colloidal solution
2.9 ± 1.5 nm 3.5 ± 1.5 nm 4.7 ± 3.5 nm 3.4 ± 1.5 nm
2.4 ± 1.0 nm
Svein Sunde, De Chen, Magnus Rønning, NTNU
Electrochemical oxidation of methanol on Pt/C Three key parameters:
1) Pt particle size
2) Support material
3) Surface oxygen groups
• Oxygen deficit surfaces provide better Pt dispersion
• Site activity is higher on the oxygen deficient catalysts than the oxygen rich catalyst
• More active than the commercial catalyst (E-TEK)
(a) (b)
Svein Sunde, De Chen, Magnus Rønning, NTNU
Challenge 7: Noble metals as long-term solution?-Dependency on scarce and expensive materials
Johnson-Matthey Platinum interim report 2012
Teknisk Ukeblad 2012
Doped carbon nanostructures as metal-free catalysts (FREECATS)
EU-FP7 NMP project coordinated by NTNU: Professor Magnus Rønning
Development of new metal-free catalysts, either in the form of bulk nanomaterials or in hierarchically organised structures capable to replace traditional noble metal-based catalysts
The application of the new materials will eliminate the use for platinum group metals and rare earth elements such as ceria used in:• Fuel cell technology (automotive applications and others, oxygen reduction reaction) • Production of light olefins (oxidative dehydrogenation of light alkanes)• Wastewater and water purification (catalytic wet air oxidation, ozonation, photocatalysis)
http://freecats.eu
10 partners, also Prototech, Bergen
Synthesis of N/P/B-doped CNT by ex-situ organic functionalization
up to 8 mg/mLDMF, 160°C, 72h
15-30 nm
Giuliano Giambastiani (CNR, Florence), Cuong Pham-Huu, CNRS Strasbourg, Charlotte Pham, SiCAT, Germany
Ex-situ doping of carbon nanotubes with different N-species
http://freecats.eu
In-situ functionalization of N-doped CNF/Graphite
Sparger
Gas mixture:- C2H6/CO/NH3, H2 and Ar
Catalyst for CNF synthesis:- 20% Fe/Al2O3
- 10% Fe/Exfoliated Graphite
N-CNT
http://freecats.eu
Reactor
Gas feed
De Chen, Magnus Rønning, NTNU
Immobilisation of Nanoparticles:-Macroscopic N/P/B-doped catalysts on silicon carbide (SiC) foams
1 µm
CNT/SiC foam CNT/SiC foamSiC foamCarbon nanotubes supported on SiC foam composite
Hierarchical structures with high effective surface area and low diffusion path
The concentration of the doped CNT or CNF can be controlled
The pore size window can be tailored to fit the downstream applications
Courtesy of SICAT
http://freecats.eu
Summary• Nanomaterials are already playing an important role in
energy and environmental technology
• Mastering synthesis and properties at atomic level is necessary for:• Bringing existing processes to a new level• Introducing new technologies
• Highly competitive discipline• National priorities required
• Need for short-term and long-term solutions • Parallel development