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Nanotechnology and Photocatalysis in
Cementitious Materials
2nd International Symposium on Nanotechnology in
Construction Bilbao, November 16th, 2005
Luigi Cassar
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Cement and TiO2

• Within the framework of a strategy aimed at
  remedying environmental pollution through the use
  of construction materials containing
  photocatalysts, a model comprising nanometric
  titanium dioxide mainly in the form of anatase
  and cement was investigated since 1995
• Commercialization of photocatalytic cement
  started in 2004
• Cement was proven to be an ideal substrate for
  the photocatalytic action of TiO2

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TiO2 applications in cementitious materials


Desoiling applications
Depolluting applications
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Practical applications
Dives in Misericordia Church, Roma (2003)
Cement White TX Millennium
Architect Richard Meier Contractor Vicariato
di Roma
Desoiling applications
5
Practical applications
Cité de la Musique et des Beaux Arts à Chambéry
(2000)
Cement Grey TX Millennium
Architect Yann Keromnès, Aurélio Galfetti,
François CussonContractor Mairie de
Chambéry
Desoiling applications
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Practical applications
Private buildings close to Bergamo (1997-1998)
Rasante prepared by White TX Millennium
Desoiling applications
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Colorimetric tests using laboratory pollutants
Bromcresol Green (pH indicator) pH gt 5.4 blue
Rhodamine B (red dye)
Desoiling applications
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Colorimetric tests using laboratory pollutants
The results are expressed in the CIE LAB system
with L, a and bcolorimetric parameters . A
convenient criteria to express and compare
activity levels obtained for different materials
is the dye destruction velocity Va, calculated
between 0 and 3 h according to the following
formula (identically for all parameters L, a,
b) With A, B, C and D are parameters
which are determined by fitting experimental
curves.
Desoiling applications
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Colorimetric test on different cement/TiO2 samples
Activity
Exposition time (hours)
Desoiling applications
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Depolluting applications
PM10, PM2,5 NOx, VOC Ozone
Vehicles
City
Emission Control Technology
Dangerous pollutants in the air Dioxins
Environmental Purification Technology
Emissions from medium/ little incinerators
Floor
Rivers, lakes
Formaldehyde Toluene Insecticides
Buidings / Houses
Internals
See also Photocatalysis Science and
TechnologyM. Kaneko-I.Okura -2002
Depolluting applications
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Depolluting applications

• Examples of pollutants which can be abated by
  the system Cement - TiO2 due to photocatalytic
  action
• NOx
• SOx
• NH3
• CO
• VOC (benzene, toluene, etc.)
• Metyl Mercaptan
• Organic chlorides
• Aromatic compounds
• Acetaldehyde
• Formaldehyde

Depolluting applications
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NO Photooxydation by TX Millennium



Data by ISPRA

120.00

60' UV lamp
on

100.00

84.03

80.00

77.20


69.12


60.00

40.00

20.00

0.68

0.00










0
50
100
150
200
250
300
350
400
450
Temps/min

Perte de la chambre

Morier normal

Mortier avec TX Millennium

Perte de la chambre UV

Depolluting applications
PICADA project
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Application tests
Segrate
Calusco
Depolluting applications
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Experimental test in Segrate
About 5000 m2 of area LUX 100.000 Wind speed
0,7m/sec about 1200 vehicles/hour
TX Millennium
Asphalt
128.5
54.8
57
Depolluting applications
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TiO2 nanoparticles in cementitious matrix
Table 1 Different types of TiO2 in anatase form
having different Mean Surface Area
Data from EP 1405835 (2002) Inventors Cassar,
Colombet, Guillot, Cassat, Bonafous
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TiO2 nanoparticles in cementitious matrix
Fig. 1 Titanium Dioxide sample A
Scanning Electron Microscope (SEM) Mod. LEO
1450VP
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TiO2 nanoparticles in cementitious matrix
Fig. 2 Titanium Dioxide sample C
Scanning Electron Microscope (SEM) Mod. LEO
1450VP
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TiO2 nanoparticles in cementitious matrix
Fig. 3 Titanium Dioxide sample C
Scanning Electron Microscope (SEM) Mod. LEO
1450VP
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TiO2 nanoparticles in cementitious matrix
Table 2 Different photocatalytic activity
Data from EP 1405835 (2002) Inventors Cassar,
Colombet, Guillot, Cassat, Bonafous
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TiO2 nanoparticles in cementitious matrix
Table 3 Synergistic effect between A and C
Data from EP 1405835 (2002) Inventors Cassar,
Colombet, Guillot, Cassat, Bonafous
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TiO2 nanoparticles in cementitious matrix
Table 4 Synergistic effect between B and C
Data from EP 1405835 (2002) Inventors Cassar,
Colombet, Guillot, Cassat, Bonafous
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Conclusions

• The surface of building elements containing
  photocatalyst and cement are able to maintain the
  aesthetic appearance unchanged over time
• The photocatalytic system cement/nanometric
  TiO2 has been confirmed as an efficient
  pollutant abating tool both in the lab and in the
  field
• A massive use of photocatalysts in construction
  materials is a new way of contributing to the
  reduction of the concentration of pollutants in
  urban environments
• It has been verified that the action of two
  different nanometric particle size distribution
  TiO2 shows a synergistic behaviour in a
  cementitious matrix by increasing the
  photocatalytic activity