Photooxidation of dicarboxylic acids—Part I: Effects of inorganic ions on degradation of azelaic acid

Abstract. This paper describes the optimization and validation of a new simple method for the quantitative determination of water in atmospheric particulate matter (PM). The analyses are performed by using a coulometric Karl-Fisher system equipped with a controlled heating device; different water contributions are separated by the application of an optimized thermal ramp (three heating steps: 50–120 °C, 120–180 °C, 180–250 °C). The analytical performance of the method was verified by using standard materials containing 5.55% and 1% by weight of water. The recovery was greater than 95%; the detection limit was about 20 μg. The method was then applied to NIST reference materials (NIST1649a, urban particulate matter) and to real PM10 samples collected in different geographical areas. In all cases the repeatability was satisfactory (10–15%). When analyzing the reference material, the separation of four different types of water was obtained. In real PM10 samples the amount of water and its thermal profile differed as a function of the chemical composition of the dust. Mass percentages of 3–4% of water were obtained in most samples, but values up to about 15% were reached in areas where the chemical composition of PM is dominated by secondary inorganic ions and organic matter. High percentages of water were also observed in areas where PM is characterized by the presence of desert dust. A possible identification of the quality of water released from the samples was tried by applying the method to some hygroscopic compounds that are likely contained in PM (pure SiO2, Al2O3, ammonium salts, carbohydrates and dicarboxylic acids) and by comparing the results with those obtained from field samples.

Download Full-text

Dicarboxylic acids, ω-oxocarboxylic acids, α-dicarbonyls, WSOC, OC, EC, and inorganic ions in wintertime size-segregated aerosols from central India: Sources and formation processes

Chemosphere ◽

10.1016/j.chemosphere.2016.06.107 ◽

2016 ◽

Vol 161 ◽

pp. 27-42 ◽

Cited By ~ 22

Author(s):

Dhananjay K. Deshmukh ◽

Kimitaka Kawamura ◽

Manas K. Deb

Keyword(s):

Inorganic Ions ◽

Central India ◽

Dicarboxylic Acids ◽

Formation Processes ◽

Oxocarboxylic Acids

Download Full-text

Molecular distribution and stable carbon isotopic compositions of dicarboxylic acids and related SOA from biogenic sources in the summertime atmosphere of Mt. Tai in the North China Plain

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-15069-2018 ◽

2018 ◽

Vol 18 (20) ◽

pp. 15069-15086 ◽

Cited By ~ 13

Author(s):

Jingjing Meng ◽

Gehui Wang ◽

Zhanfang Hou ◽

Xiaodi Liu ◽

Benjie Wei ◽

...

Keyword(s):

Azelaic Acid ◽

North China Plain ◽

North China ◽

Organic Aerosols ◽

Dicarboxylic Acids ◽

Stable Carbon ◽

Δ13c Values ◽

Carbon Isotopic ◽

The North ◽

The North China Plain

Abstract. Molecular distributions and stable carbon isotopic (δ13C values) compositions of dicarboxylic acids and related secondary organic aerosols (SOA) in PM2.5 aerosols collected on a day/night basis at the summit of Mt. Tai (1534 m a.s.l.) in the summer of 2016 were analyzed to investigate the sources and photochemical aging process of organic aerosols in the forested highland region of the North China Plain. The molecular distributions of dicarboxylic acids and related SOA are characterized by the dominance of oxalic acid (C2), followed by malonic (C3), succinic (C4) and azelaic (C9) acids. The concentration ratios of C2 ∕ C4, diacid-C ∕ OC and C2 ∕ total diacids are larger in the daytime than in the nighttime, suggesting that the daytime aerosols are more photochemically aged than those in the nighttime due to the higher temperature and stronger solar radiation. Both ratios of C2 ∕ C4 (R2>0.5) and C3 ∕ C4 (R2>0.5) correlated strongly with the ambient temperatures, indicating that SOA in the mountaintop atmosphere are mainly derived from the photochemical oxidation of local emissions rather than long-range transport. The mass ratios of azelaic acid to adipic acid (C9 ∕ C6), azelaic acid to phthalic aid (C9 ∕ Ph) and glyoxal to methylglyoxal (Gly ∕ mGly) and the strong linear correlations of major dicarboxylic acids and related SOA (i.e., C2, C3, C4, ωC2, Pyr, Gly and mGly) with biogenic precursors (SOA tracers derived from isoprene, α/β-pinene and β-caryophyllene) further suggest that aerosols in this region are mainly originated from biogenic sources (i.e., tree emissions). C2 concentrations correlated well with aerosol pH, indicating that particle acidity favors the organic acid formation. The stable carbon isotopic compositions (δ13C) of the dicarboxylic acids are higher in the daytime than in the nighttime, with the highest value (-16.5±1.9 ‰) found for C2 and the lowest value (-25.2±2.7 ‰) found for C9. An increase in δ13C values of C2 along with increases in C2 ∕ Gly and C2 ∕ mGly ratios was observed, largely due to the isotopic fractionation effect during the precursor oxidation process.

Download Full-text

Piezoelectric crystal microbalance measurements of enthalpy of sublimation of C<sub>2</sub>–C<sub>9</sub> dicarboxylic acids

Atmospheric Measurement Techniques ◽

10.5194/amt-9-655-2016 ◽

2016 ◽

Vol 9 (2) ◽

pp. 655-668 ◽

Cited By ~ 1

Author(s):

F. Dirri ◽

E. Palomba ◽

A. Longobardo ◽

E. Zampetti

Keyword(s):

Oxalic Acid ◽

Azelaic Acid ◽

Dicarboxylic Acids ◽

Enthalpy Of Sublimation ◽

Effusion Cell ◽

Piezoelectric Crystal ◽

Volatile Organic ◽

Set Up ◽

Good Agreement

Abstract. We present here a novel experimental set-up that is able to measure the enthalpy of sublimation of a given compound by means of piezoelectric crystal microbalances (PCMs). The PCM sensors have already been used for space measurements, such as for the detection of organic and non-organic volatile species and refractory materials in planetary environments. In Earth atmospherics applications, PCMs can be also used to obtain some physical–chemical processes concerning the volatile organic compounds (VOCs) present in atmospheric environments. The experimental set-up has been developed and tested on dicarboxylic acids. In this work, a temperature-controlled effusion cell was used to sublimate VOC, creating a molecular flux that was collimated onto a cold PCM. The VOC recondensed onto the PCM quartz crystal, allowing the determination of the deposition rate. From the measurements of deposition rates, it has been possible to infer the enthalpy of sublimation of adipic acid, i.e. ΔHsub : 141.6 ± 0.8 kJ mol−1, succinic acid, i.e. 113.3 ± 1.3 kJ mol−1, oxalic acid, i.e. 62.5 ± 3.1 kJ mol−1, and azelaic acid, i.e. 124.2 ± 1.2 kJ mol−1. The results obtained show an accuracy of 1 % for succinic, adipic, and azelaic acid and within 5 % for oxalic acid and are in very good agreement with previous works (within 6 % for adipic, succinic, and oxalic acid and within 11 % or larger for azelaic acid).

Download Full-text

Size distributions of dicarboxylic acids, ketoacids, α-dicarbonyls, sugars, WSOC, OC, EC and inorganic ions in atmospheric particles over Northern Japan: implication for long-range transport of Siberian biomass burning and East Asian polluted aerosols

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-10-6713-2010 ◽

2010 ◽

Vol 10 (3) ◽

pp. 6713-6754 ◽

Cited By ~ 1

Author(s):

S. Agarwal ◽

S. G. Aggarwal ◽

K. Okuzawa ◽

K. Kawamura

Keyword(s):

Organic Carbon ◽

Biomass Burning ◽

Fine Particles ◽

Source Region ◽

Inorganic Ions ◽

Dicarboxylic Acids ◽

Water Soluble ◽

Anthropogenic Source ◽

Night Time ◽

Chemical Tracers

Abstract. To better understand the size-segregated chemical composition of aged organic aerosols in the western Pacific rim, day- and night-time aerosol samples were collected in Sapporo, Japan during summer 2005 using Andersen impactor sampler with 5 size bins: <1.1, 1.1–2.0, 2.0–3.3, 3.3–7.0, >7.0 μm. Samples were analyzed for the molecular compositions of dicarboxylic acids, ketoacids, α-dicarbonyls, and sugars, together with water-soluble organic carbon (WSOC), organic carbon (OC), elemental carbon (EC) and inorganic ions. Based on the analyses of backward trajectory and chemical tracers, we found that during campaign, the air masses were arrived from Siberia (biomass burning source region) on 8–9 August, China (anthropogenic source region) on 9–10 August and from the East China Sea/Sea of Japan (a mixed source receptor region) on 10–11 August. Most of the diacids, ketoacids, dicarbonyls, levoglucosan, WSOC, and inorganic ions, i.e., SO42−, NH42+ and K+ were enriched in fine particles (PM1.1) whereas Ca2+, Mg2+ and Cl− peaked in coarse sizes (>1.1 μm). Interestingly, OC, most sugar compounds and NO4

Download Full-text

Size distributions of dicarboxylic acids, ketoacids, α-dicarbonyls, sugars, WSOC, OC, EC and inorganic ions in atmospheric particles over Northern Japan: implication for long-range transport of Siberian biomass burning and East Asian polluted aerosols

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-5839-2010 ◽

2010 ◽

Vol 10 (13) ◽

pp. 5839-5858 ◽

Cited By ~ 115

Author(s):

S. Agarwal ◽

S. G. Aggarwal ◽

K. Okuzawa ◽

K. Kawamura

Keyword(s):

Chemical Composition ◽

Organic Carbon ◽

Long Range ◽

Biomass Burning ◽

North Pacific ◽

Western North Pacific ◽

Source Region ◽

Inorganic Ions ◽

Dicarboxylic Acids ◽

Pacific Rim

Abstract. To better understand the size-segregated chemical composition of aged organic aerosols in the western North Pacific rim, day- and night-time aerosol samples were collected in Sapporo, Japan during summer 2005 using an Andersen impactor sampler with 5 size bins: Dp<1.1, 1.1–2.0, 2.0–3.3, 3.3–7.0, >7.0 μm. Samples were analyzed for the molecular composition of dicarboxylic acids, ketoacids, α-dicarbonyls, and sugars, together with water-soluble organic carbon (WSOC), organic carbon (OC), elemental carbon (EC) and inorganic ions. Based on the analyses of backward trajectories and chemical tracers, we found that during the campaign, air masses arrived from Siberia (a biomass burning source region) on 8–9 August, from China (an anthropogenic source region) on 9–10 August, and from the East China Sea/Sea of Japan (a mixed source receptor region) on 10–11 August. Most of the diacids, ketoacids, dicarbonyls, levoglucosan, WSOC, and inorganic ions (i.e., SO42−, NH4+ and K+) were enriched in fine particles (PM1.1) whereas Ca2+, Mg2+ and Cl− peaked in coarse sizes (>1.1 μm). Interestingly, OC, most sugar compounds and NO3− showed bimodal distributions in fine and coarse modes. In PM1.1, diacids in biomass burning-influenced aerosols transported from Siberia (mean: 252 ng m−3) were more abundant than those in the aerosols originating from China (209 ng m−3) and ocean (142 ng m−3), whereas SO42− concentrations were highest in the aerosols from China (mean: 3970 ng m−3) followed by marine- (2950 ng m−3) and biomass burning-influenced (1980 ng m−3) aerosols. Higher loadings of WSOC (2430 ng m−3) and OC (4360 ng m−3) were found in the fine mode, where biomass-burning products such as levoglucosan are abundant. This paper presents a case study of long-range transported aerosols illustrating that biomass burning episodes in the Siberian region have a significant influence on the chemical composition of carbonaceous aerosols in the western North Pacific rim.

Download Full-text