Document Type : Research Paper


1 Institute of Northern Technical University, Department of Chemical and Oil Industries, Mosul, Iraq

2 university of Technology, Chemical Engineering Department, Baghdad, Iraq

3 University of Technology, Chemical Engineering Department, Baghdad, Iraq

4 Chemical Eng.Dep. Altrath University , Baghdad

5 Turath University College, Department of Oil & Gas Refining Engineering, Baghdad, Iraq

6 Medical instrumentation Techniques Engineering , Alhikma University College

7 Al-Turath University College, Department of Oil & Gas Refining Engineering, Baghdad, Iraq

8 University of Technology, Mechanical Engineering Department, Baghdad, Iraq

9 Mechanical Engineering and Energy Processes, Southern Illinois University


Road transportation in urban areas may be considered a major source of environmental pollution. The purpose of this study is to determine the effectiveness of the oxidation of carbon dioxide gas emitted by an internal combustion engine. This is achieved using an asphaltic pavement coated with Cu/TiO2 nanoparticles by spraying and irradiating with white light under ambient conditions to reduce the air pollution problem (carbon monoxide) caused by vehicles. Using electron microscopy, energy dispersive spectroscopy, and Fourier transform infrared spectroscopy, we determined the physicochemical and morphological characteristics of the photocatalyst. Following the characterization study, the photo-catalytic activity of the asphalt materials was determined. Experimental results showed that CO conversion positively depends on different conditions, including Cu loading, light intensity, and relative humidity. However, the gas flow rate showed a different trend. The optimal operating parameters were determined as follows: Cu loading (3.6% by weight), a flow rate of gas (1 L/min), relative humidity (30%), and light intensity (35 W/m2) to ensure the best photo-oxidation efficiency of 56.4% after three hours of operation. A mathematical correlation related to CO2 removal as a function of different operating conditions was found with a correlation factor of 0.975 and a variance equal to 0.964. Moreover, a kinetic pathway for photo-oxidation of CO at various oxygen concentrations was presented.

Graphical Abstract


  • The effectiveness of the oxidation of carbon dioxide gas emitted by an internal combustion engine was studied.
  • The CO conversion positively depends on Cu loading, light intensity, and relative humidity.
  • The best photo-oxidation efficiency of 56.4% was achieved after three hours of operation.


Main Subjects

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