On-Road Emission Characteristics of Volatile Organic Compounds from Light-Duty Diesel Trucks Meeting Different Emission Standards

On-road tailpipe volatile organic compounds (VOCs) were sampled from light-duty diesel trucks compliant with Euro III to V, and a total of 102 VOC species were quantified. The composition characteristics and carbon number distributions were investigated, and the contribution of individual VOC to ozone formation potentials (OFPs) was weighted. Results showed that alkanes were the major VOC species, accounting for approximately 65.5%. VOC emissions decreased significantly as the standards became stricter, especially for alkanes and aromatics; and the VOC emissions on highway were much lower than those on urban roads. Carbon number distribution of VOCs was mainly concentrated in C3-C4 and C10-C12. Aromatics were the major contributors to ozone formation, taking up 49.3-57.6% of the total OFPs, and naphthalene, 1-butene, dodecane, 1,2,3-trimethylbenzene and 2-propenal were the top five species. The information provided insight into the tailpipe VOC emission characteristics, and may help decision makers drafting related emission policies.

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Volatile organic compounds from a mixed fleet with numerous E10-fuelled vehicles in a tunnel study in China: Emission characteristics, ozone formation and secondary organic aerosol formation

Environmental Research ◽

10.1016/j.envres.2021.111463 ◽

2021 ◽

pp. 111463

Author(s):

Boqiang Jin ◽

Rencheng Zhu ◽

Hui Mei ◽

Menglei Wang ◽

Lei Zu ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Secondary Organic Aerosol ◽

Organic Aerosol ◽

Emission Characteristics ◽

Ozone Formation ◽

Aerosol Formation ◽

Volatile Organic ◽

Secondary Organic Aerosol Formation

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Species and characteristics of volatile organic compounds emitted from an auto-repair painting workshop

Scientific Reports ◽

10.1038/s41598-021-96163-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

M. Y. Song ◽

H. Chun

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Large Scale ◽

Butyl Acetate ◽

Small Scale ◽

Indoor Environments ◽

Voc Emissions ◽

Volatile Organic ◽

Before And After ◽

Adsorption Systems

AbstractVolatile organic compounds (VOCs) are secondary pollutant precursors having adverse impacts on the environment and human health. Although VOC emissions, their sources, and impacts have been investigated, the focus has been on large-scale industrial sources or indoor environments; studies on relatively small-scale enterprises (e.g., auto-repair workshops) are lacking. Here, we performed field VOC measurements for an auto-repair painting facility in Korea and analyzed the characteristics of VOCs emitted from the main painting workshop (top coat). The total VOC concentration was 5069–8058 ppb, and 24–35 species were detected. The VOCs were mainly identified as butyl acetate, toluene, ethylbenzene, and xylene compounds. VOC characteristics differed depending on the paint type. Butyl acetate had the highest concentration in both water- and oil-based paints; however, its concentration and proportion were higher in the former (3256 ppb, 65.5%) than in the latter (2449 ppb, 31.1%). Comparing VOC concentration before and after passing through adsorption systems, concentrations of most VOCs were lower at the outlets than the inlets of the adsorption systems, but were found to be high at the outlets in some workshops. These results provide a theoretical basis for developing effective VOC control systems and managing VOC emissions from auto-repair painting workshops.

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Water-Enhanced Flux Changes under Dynamic Temperatures in the Vertical Vapor-Phase Diffusive Transport of Volatile Organic Compounds in Near-Surface Soil Environments

Sustainability ◽

10.3390/su13126570 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6570

Author(s):

Asma Akter Parlin ◽

Monami Kondo ◽

Noriaki Watanabe ◽

Kengo Nakamura ◽

Mizuki Yamada ◽

...

Keyword(s):

Air Quality ◽

Volatile Organic Compounds ◽

Organic Compounds ◽

Vapor Phase ◽

Inverse Correlation ◽

Diffusive Transport ◽

Near Surface ◽

Voc Emissions ◽

Transport Behavior ◽

Volatile Organic

The quantitative understanding of the transport behavior of volatile organic compounds (VOCs) in near-surface soils is highly important in light of the potential impacts of soil VOC emissions on the air quality and climate. Previous studies have suggested that temperature changes affect the transport behavior; however, the effects are not well understood. Indeed, much larger changes in the VOC flux under in situ dynamic temperatures than those expected from the temperature dependence of the diffusion coefficients of VOCs in the air have been suggested but rarely investigated experimentally. Here, we present the results of a set of experiments on the upward vertical vapor-phase diffusive transport of benzene and trichloroethylene (TCE) in sandy soils with water contents ranging from an air-dried value to 10 wt% during sinusoidal temperature variation between 20 and 30 °C. In all experiments, the flux from the soil surface was correlated with the temperature, as expected. However, the changes in flux under wet conditions were unexpectedly large and increased with increasing water content; they were also larger for TCE, the volatility of which depended more strongly on the temperature. Additionally, the larger flux changes were accompanied by a recently discovered water-induced inverse correlation between temperature and flux into the overlying soil. These results demonstrated that the flux changes of VOCs under dynamic temperatures could be increased by volatilization-dissolution interactions of VOCs with water. Future extensive studies on this newly discovered phenomenon would contribute to a better understanding of the impacts of soil VOC emissions on the air quality and climate.

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Spatial Distribution, Source Apportionment, Ozone Formation Potential, and Health Risks of Volatile Organic Compounds over a Typical Central Plain City in China

Atmosphere ◽

10.3390/atmos11121365 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1365

Author(s):

Kun He ◽

Zhenxing Shen ◽

Jian Sun ◽

Yali Lei ◽

Yue Zhang ◽

...

Keyword(s):

Volatile Organic Compounds ◽

Source Apportionment ◽

Organic Compounds ◽

Health Risks ◽

Urban Areas ◽

High Time Resolution ◽

Ozone Formation ◽

Industrial Site ◽

Industrial Emissions ◽

Volatile Organic

The profiles, contributions to ozone formation, and associated health risks of 56 volatile organic compounds (VOCs) species were investigated using high time resolution observations from photochemical assessment monitoring stations (PAMs) in Luoyang, China. The daily averaged concentration of total VOCs (TVOCs) was 21.66 ± 10.34 ppbv in urban areas, 14.45 ± 7.40 ppbv in suburbs, and 37.58 ± 13.99 ppbv in an industrial zone. Overall, the VOCs levels in these nine sites followed a decreasing sequence of alkanes > aromatics > alkenes > alkyne. Diurnal variations in VOCs exhibited two peaks at 8:00–9:00 and 19:00–20:00, with one valley at 23:00–24:00. Source apportionment indicated that vehicle and industrial emissions were the dominant sources of VOCs in urban and suburban sites. The industrial site displayed extreme levels, with contributions from petrochemical-related sources of up to 38.3%. Alkenes and aromatics displayed the highest ozone formation potentials because of their high photochemical reactivity. Cancer and noncancer risks in the industrial site were higher than those in the urban and suburban areas, and USEPA possible risk thresholds were reached in the industrial site, indicating PAMs VOC–related health problems cannot be ignored. Therefore, vehicle and industrial emissions should be prioritized when considering VOCs and O3 control strategies in Luoyang.

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