Identification of two main origins of intermediate-volatility organic compound emissions from vehicles in China through two-phase simultaneous characterization | JoVE Visualize

Identification of two main origins of intermediate-volatility organic compound emissions from vehicles in China through two-phase simultaneous characterization

Yuanxiang Liu¹, Yingjie Li², Zibing Yuan¹

¹School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.

Environmental Pollution (Barking, Essex : 1987)|April 4, 2021

View abstract on PubMed

Summary

Vehicle emissions of intermediate-volatility organic compounds (IVOCs) were studied. Diesel vehicles emitted significantly more IVOCs than gasoline vehicles, with lubricating oil being a key contributor to particle-phase IVOCs.

Area of Science:

Atmospheric Chemistry
Environmental Science
Automotive Engineering

Background:

Intermediate-volatility organic compounds (IVOCs) from vehicle emissions contribute to air pollution.
Understanding IVOC partitioning between gas and particle phases is crucial for accurate emission assessments.

Purpose of the Study:

To characterize gas- and particle-phase IVOC emissions from gasoline and diesel vehicles.
To identify the primary sources of IVOCs in vehicle exhaust.
To assess the impact of IVOCs on secondary organic aerosol (SOA) formation.

Main Methods:

Dynamometer testing of gasoline and diesel vehicles in Guangzhou, China.
Simultaneous characterization of gas- and particle-phase IVOCs.
Chemical composition and volatility distribution analysis.

Main Results:

Diesel vehicles emitted ~16 times more IVOCs than gasoline vehicles, primarily in the particle phase (unresolved complex mixture).
Gas-phase IVOCs originated mainly from fuel, while particle-phase IVOCs were linked to lubricating oil.
IVOCs significantly contributed to secondary organic aerosol (SOA) formation, exceeding primary organic aerosol (POA) emissions.

Conclusions:

Lubricating oil is a critical source of particle-phase IVOCs.
Stricter emission standards, particularly China VI, are necessary to effectively reduce IVOC emissions and subsequent SOA production.
Accelerating the adoption of the latest emission standards is vital for mitigating vehicle-related air pollution in China.