24/04/121 starbons and their applications dr. vitaliy budarin
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Starbons and their applications
Dr. Vitaliy Budarin
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Contents
1. Introduction to mesoporous materials
2. Starbon technology
3. Starbon applications:• Nanotechnology• Catalysis• Water treatment• Chromatography
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Porous materials
Pore type Pore Size Condensation
mechanismType of
Adsorption
Micropore < 2 nmThree-
dimensional Non-specific
Mesopore ≥ 2 ≤ 50 nm Capillary Specific
Macropore > 50 nm No condensation -
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Potential applications of mesoporous materials
Adsorption
Filtration
Chromatography
Catalysis
ElectrochemistryNanotechnology
Sensors
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Synthesis of Mesoporus materials
Technologies Limitation: •Costly•Wasteful •Complicated•Time consuming•Limited
functionality
Benefits: regular & well ordered
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Native mesoporous materials
Nature is adept at the self assembly of organic polymers in a wide range of structural and storage roles in higher plants
Is porous structures of native
materials accessible for chemistry?
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Expanded starch formation
Chem.Commun, 2002, 2632
Methodology utilises:• Starch
o inexpensive, biomass• green solvents
o water, ethanol and ScCO2
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Starbonisation
1000C 7000C
Starch Mesoporous Carbon
Starbons
Starbon Properties :
Tuneable surface functionality High mesoporosity (up to 2.0 cm3/g) High surface areas (up to 500 m2/g) Controllable electrical conductivity Particulate / monolithic forms
Angew. Chem. Int. Ed, 2006 45 3782
H+
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MesoporeMicropore
10 nm
1 nm
Starbon. Texture properties
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Starbon. Textural properties.Influence of the preparation temperature.
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A) 4000C StarbonB) 6000C Starbon
SEM of Starbons
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Nanotechnolo
gy
Chrom
atogra
phy
Applications
Acid cata
lysis
Organic adsorp
tion
Metal a
dsorptio
n
Starbons functionality
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Starbon Surface modification
Starbon surface can be modified with:
Halogens
Sulfuric acid
Amines
Chitosan
Phosphates
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Starbon application: Synthesis of nanoparticles
Green Chemistry 10 (4), 382-387, 2008
• The nanoparticle size distribution was controllable by pore structure of Starbon
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Catalyst preparation:1) Sulfonation: 400C, 2 h. 2) Washing:
waterwater-ethanol mixture, 800C
Succinic acid esterification.Starbon-350@SO3H
Starbon application: Acid catalysis in water-organic mixture
Chem.Eur.J., 2007, 13, 691414/03/11
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Rationale for activity
• Esterification should be poor in water
• Selective adsorption / exclusion of water?
• Reaction in pore / on surface• Product desorbed and stable in
aqueous environment
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Adsorption of acids. Starbon-4000C
400oC Starbon the best for succinic acidCorrelates with catalysis (?)
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Peat based soils West coast of Scotland,IrelandNorthern England
• Low Polarity favoured for silicas and Starbons
• Starbons better (high pore size )
• Best adsorbs ca. 200mg/g
Starbon application: Decolourisation of peat water
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Adsorption kineticMethylene blue
• High mesoporosity tend to increase rate of adsorption
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Starbon application: Decolourisation of peat water
Advanced Functional Materials, 20 (11), 1834-1841, 2010
• No acid catalyst
• 95% mesoporosity
• Good sugar isomer separation
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Conclusions
• Starbon technology is an overall more environmental friendly as compared to commercially available mesoporous materials
• Starbons are versatile mesoporous materials
– Functionality can be controlled by preparation method
• Starbons demonstrated great promise in: – Catalysis– Adsorption– Nano technology– Chromatography
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