VOC species and emission inventory from vehicles and their SOA formation potentials estimation in Shanghai, China

Abstract

Abstract. Volatile organic compound (VOC) species from vehicle exhausts and gas evaporation were investigated by chassis dynamometer and on-road measurements of nine gasoline vehicles, seven diesel vehicles, five motorcycles, and four gas evaporation samples. The secondary organic aerosol (SOA) mass yields of gasoline, diesel, motorcycle exhausts, and gas evaporation were estimated based on the mixing ratio of measured C2–C12 VOC species and inferred carbon number distributions. High aromatic contents were measured in gasoline exhausts and contributed comparatively more SOA yield. A vehicular emission inventory was compiled based on a local survey of on-road traffic in Shanghai and real-world measurements of vehicle emission factors from previous studies in the cities of China. The inventory-based vehicular organic aerosol (OA) productions to total CO emissions were compared with the observed OA to CO concentrations (ΔOA / ΔCO) in the urban atmosphere. The results indicate that vehicles dominate the primary organic aerosol (POA) emissions and OA production, which contributed about 40 and 60 % of OA mass in the urban atmosphere of Shanghai. Diesel vehicles, which accounted for less than 20 % of vehicle kilometers of travel (VKT), contribute more than 90 % of vehicular POA emissions and 80–90 % of OA mass derived by vehicles in urban Shanghai. Gasoline exhaust could be an important source of SOA formation. Tightening the limit of aromatic content in gasoline fuel will be helpful to reduce its SOA contribution. Intermediate-volatile organic compounds (IVOCs) in vehicle exhausts greatly contribute to SOA formation in the urban atmosphere of China. However, more experiments need to be conducted to determine the contributions of IVOCs to OA pollution in China.

Characteristics of marine shipping emissions at berth: profiles for particulate matter and volatile organic compounds

“…Among aromatics, benzene and toluene contributed approximately 9 % to the total VOC emissions. This result was consistent with a study by Huang et al (2015) on diesel emissions in Shanghai. In view of oxygenated VOCs and haloalkane contents, acetone and CH 2 Cl 2 exceeded benzene and toluene.…”

“…It was observed that the relative signal area of EC ions was higher and more widely distributed than for OC Figure 3. Comparison of SOA yields and OFP based on VOC source profiles with calculated results from previous studies Cao et al, 2015;Huang et al, 2015). The purple dots represent ships tested in this study.…”

“…It should be noted here that intermediate VOCs (IVOCs) were not identified or quantified in this study, which may cause an underestimation of the actual SOA yields. Furthermore, the VOC source profiles of three types of diesel trucks (light-, middle-and heavy-duty trucks) from Yao et al (2015) and the profiles of heavyduty diesel trucks from Huang et al (2015) were referenced to use in calculations and to compare with VOC profiles from this research. The average VOC source profile for light-duty gasoline passenger vehicles was also taken from previous research in China to make further comparisons.…”

“…Various studies have illustrated the effect of using HFO and MDO on shipping emission chemical characteristics. For black carbon (BC), using low sulfur content MDO could result in a reduction of up to 80 % of total BC emissions compared to using HFO (Lack and Corbett, 2012). A recent comparative study focused on HFO and MDO in the European sulfur emission control area (SECA) showed that a decline in sulfur content from 0.48 to 0.092 % led to a reduction of 67 % in PM mass and 80 % in SO 2 emissions (Zetterdahl et al, 2016).…”

Secondary Organic Aerosol Production from Local Emissions Dominates the Organic Aerosol Budget over Seoul, South Korea, during KORUS-AQ

“…This provides confidence that 891 the calculation described in SI 6 captures the chemical production of SOA over Seoul. Also, the 892 difference between the estimated and measured OA is comparable to, or better than, found in other 893 studies that utilized a similar modeling approaches (Dzepina et al, 2009;Zhao et al, 2014Zhao et al, , 2016894 Hayes et al, 2015;Huang et al, 2015;Ma et al, 2017), and within the uncertainty of the measured 895 OA (38%, 2σ). 896…”