Air and Water Impacts of TX Active Concrete Pavement

St. Louis, Missouri, Rte. 141

TX Active Photocatalytic Cement• Developed by Italcementi • Contains titanium dioxide (a photocatalyst)

in anatase form• Abates smog-forming emissions (e.g.,

nitrogen oxides)• Self-cleaning, maintains surface color

NOX

siteNOXads

NO3-H+

●OH

Runoff water with a projected low NO3

- presence

Water

Adsorbs on ‘active’ site1

Oxidized by photo-generated hydroxyl ions

2

Washed from surface3

Photocatalytic Concrete

TX Active Research Project Overview• Relocated Rte 141 project, Chesterfield, MO

46,450 anticipated AADT Near St. Louis (population of 3,000,000))

• 1500 foot test section (placed in Oct 2011) Two-lift construction (2” on 7”) TX Active cement in top lift TX Active cement in pervious concrete shoulder

• Will monitor (over a 1-year period) Air quality (NOx, NO2, NO) Water quality (BOD, COD, nitrate)

• Funded by:

TX Active Project Site

TX Active

Control Air Sampling

Water Sampling

TX Active Project Photos