Abstract:
The environment in our cities is increasingly being polluted as a result of the escalating
population and subsequent upsurge in the use of vehicles. The emission of greenhouse
gases through use of fossil fuels has been on the rise mainly because a lot of it has been
burnt during transportation or for industrial purposes.
The use of surface chemistry in heterogeneous catalyst technology has facilitated the
creation of catalytic methods for managing and reducing pollution. Catalytic converters are
one technological approach to controlling vehicle emissions.
In this study, we present the performance of a dual bed catalytic converter featuring a WO3-
based catalyst on Bed #1 and a composite oxide Co3O4/TiO2 on Bed #2, both utilizing a
steel wire mesh substrate.
The dual bed catalysts have been synthesized via hydrothermal and co-precipitation
methods. They were then tested for their effectiveness in oxidizing CO and reducing NOx
emissions from a 169 cm3 engine mounted on an engine test bed with a dynamometer.
The evaluation was supposed to be conducted under simulated real driving conditions (idle,
acceleration, and deceleration) by varying the torque/load on the engine and measuring the
total distance traveled, with the help of RPM monitoring in accordance with the WLTP
(Worldwide Harmonized Light Vehicles Test Procedure).
Along the exercise, it was observed that engine under test was discharging exhaust gases
at lower temperatures below 150°C which was quite lower than expected range of
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Temperature was above 200°C to 300°C, supplementary electric heating element was
subsequently added to raise temperature of exhaust to investigate the performance of dual
bed catalyst assembly at constant high load / high torque conditions.
The results revealed the combined effect of dual bed catalyst, impact could be due to
existence of a catalytic synergistic effect of Co3O4 / TiO2 and WO3 beds. Maximum
Emission rate after treatment measured in case of CO and NOx is 1020 ppm & 48 ppm
respectively. Overall Conversion Efficiency Demonstrated for CO Levels reduced 83%
and NOx Levels reduced 72%.
