The Characteristics of Ambient Non-Methane Hydrocarbons (NMHCs) in Lanzhou, China

• DOI: 10.3390/atmos10120745
• Publication Date: 2019-11-26T15:57:27Z
• Authors: Yajun Wu; Jun Hu; Han Wang; Hui Li; Hefeng Zhang; Fahe Chai; Shulan Wang
• Keywords: Petrochemical; Isopentane

Non-methane hydrocarbons (NMHCs) from four sampling sites in Lanzhou, a petrochemical industrialized city northwest China, was sampled by stainless steel canisters and measured gas chromatography–mass selective detection/flame ionization detection (GC–MSD/FID) May June of 2017. Based on these results, the contributions NMHCs to ozone (O3) secondary organic aerosols (SOA), differences tracer ratios, source apportionment principal component analysis (PCA) were analyzed. The results showed that total concentration Lanzhou 48.4 ± 48.3 ppbv (parts per billion volume) during observation it higher (78.6 ppbv) than (37.8 ppbv); highest observed industrial areas. Alkanes dominant group at all account for more 60% NMHCs, while isopentane, n-butane n-pentane, propane ethane major compounds. Additionally, have made great O3 SOA generation S1 site area contributed most both them. Propene, toluene, ethylbenzene n-pentane found be reactive with relatively high formation. Aromatics carbon alkanes contributors formation potential (SOAp) (i.e., m,p-xylene, dodecane, undecane, n-tanane, benzene ethylbenzene) Lanzhou. specific volatile compounds (VOCs) ratio method PCA modem, greatly affected surrounding sources consisted industry, vehicle emissions, solvent usage combustion sources, which 33.9%, 31.6%, 19.2% 7.9% monitored respectively. From different sites, though influence regional transport not very significant whole, also nonindustrial areas based xylene ethyl-benzene (X/E), especially S4 site; emission less important compared industries S1, as characterized toluene (T/B) ratios. However, has S4. Overall, local emissions are main industry distribution whole region.