Open AccessCharacterization of water‐soluble organic compounds in atmospheric aerosol: A new approach
Author(s) -
Decesari Stefano,
Facchini Maria Cristina,
Fuzzi Sandro,
Tagliavini Emilio
Publication year - 2000
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1999jd900950
Subject(s) - aerosol , chemistry , fraction (chemistry) , proton nmr , total organic carbon , carbon fibers , characterization (materials science) , chemical composition , organic chemistry , materials science , nanotechnology , composite number , composite material
A new methodological approach is proposed to characterize aerosol water‐soluble organic compounds (WSOC). Real aerosol and fog water samples were subjected to a procedure based on a combination of Chromatographic separations, functional group investigation by proton nuclear magnetic resonance (HNMR), and total organic carbon determination. The complex mixture of aerosol/fog WSOC was separated by a Chromatographic procedure into three main classes of compounds: (1) neutral/basic compounds; (2) mono‐ and di‐carboxylic acids; (3) polyacidic compounds. Characterization by HNMR spectroscopy showed that fraction 1 is mainly composed of polyols or polyethers, fraction 2 is mainly composed of hydroxylated aliphatic acidic compounds, while fraction 3 is composed of highly unsaturated polyacidic compounds of predominantly aliphatic character, with a minor content of hydroxyl‐ groups. Quantitative data on the three classes of compounds were then derived from total organic carbon analysis, showing that the three separated fractions together account for 77% (in terms of C) of the total WSOC concentration of a fog water sample. Further quantitative information on the functional groups present in the three separated fractions can be obtained from HNMR spectra. This newly proposed approach to aerosol WSOC characterization provides comprehensive and synthetic information on aerosol organic composition which can be helpful for modeling purposes and is also particularly useful when aerosol chemical mass closure is pursued.