Functional Materials Based on Active Carbon and Titanium Dioxide in Fog Seal

Area of Science:

• Materials Science
• Environmental Engineering
• Photocatalysis

Background:

• Titanium dioxide (TiO2) is used in asphalt concrete to degrade nitrogen oxides (NOx) from vehicle emissions.
• Automobile exhaust poses risks to road traffic environmental quality and human health.
• There is a need for effective pavement materials to mitigate air pollution.

Purpose of the Study:

• To develop a photocatalytic pavement coating by combining titanium dioxide and activated carbon within a Sand-fog seal.
• To enhance the degradation efficiency of nitrogen dioxide (NO2) from vehicle exhaust.
• To evaluate the material's dispersion, photocatalytic performance, and skid resistance.

Main Methods:

• Synthesized a composite material of titanium dioxide and activated carbon modified with a titanate coupling agent.
• Conducted indoor experiments to test NO2 degradation efficiency under varying component ratios, coupling agents, and dosages.
• Utilized Scanning Electron Microscope (SEM) for dispersion analysis and British Pendulum tests for skid resistance.

Main Results:

• Optimal photocatalytic efficiency was achieved with an activated carbon to titanium dioxide ratio of 0.6.
• Titanate coupling agent modification ensured good dispersion of the composite material in the Sand-fog seal.
• A 10% composite material dosage in the fog seal yielded a peak photocatalytic efficiency of 23.9%.
• The material exhibited good skid resistance.
• A field trial on a concrete roadway in Tianjin showed improved NOx degradation compared to the original road.

Conclusions:

• The developed photocatalytic pavement coating effectively degrades nitrogen oxides.
• The composite material demonstrates good dispersion, photocatalytic activity, and skid resistance.
• The technology is feasible for practical implementation in road construction to improve air quality.