Aerosol measurements (PM 2.5) in Sydney atmosphere with PILS-IC

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1 Branch 2. Water wastewater, air, environmental protection. Keywords IC / 850 / PILS / anions / cations / Metrosep A Supp / Metrosep C4-100 / Particle into Liquid Sampler / aerosol / chloride / nitrite / nitrate / sulphate / sodium / ammonium / potassium / calcium / magnesium / branch 2 Summary Aerosols are a major concern for climate and health issues. Atmospheric aerosol particles influence the climate system directly by scattering and absorbing solar radiation, and indirectly by acting as cloud condensation nuclei. Apart from black carbon aerosol, aerosols cause a negative radiative force at the top of the atmosphere and substantially mitigate the warming caused by greenhouse gases. In the future, tightening of controls on anthropogenic aerosol and precursor vapour emissions to achieve higher air quality may weaken this beneficial effect. Natural aerosols, mainly through volcanic activity, might affect future warming too. The effects of inhaling particulate matter that have been widely studied in humans and animals now include asthma, lung cancer, cardiovascular issues, respiratory diseases, birth defects, and premature death. The size of the particle is a key determinant of where in the respiratory tract the particle will come to rest when inhaled. Because of their small size, particles of the order of ~10 micro meters or less (PM10 or PM2.5) can penetrate the deepest part of the lungs such as the bronchioles or alveoli. Larger particles are generally filtered in the nose and throat via cilia and mucus, but particulate matter smaller than about 2.5 micro meters, referred to as PM2.5, can settle in the bronchi and lungs and cause health problems. Some particulates occur naturally, originating from volcanoes, dust storms, forest and grassland fires, living vegetation, and sea spray. Human activities, such as the burning of fossil fuels in vehicles, power plants and various industrial processes also generate significant amounts of particulates Reagents Sodium bicarbonate/sodium carbonate concentrate 64 mm Na 2CO 3 and 20 mm NaHCO 3 Fluka # Sulfuric acid, CAS Instruments Nitric acid/ Dipicolinic acid concentrate 14 mm C 7H 5NO 4 and 34 mm HNO 3, Fluka # Ultrapure water, resistivity >18 MΩ cm (25 C), type I grade (ASTM D1193) Single component Anion and cation standards for IC. 850 Professional IC AnCat MCS IC conductivity detector Particle Into Liquid Sampler ADI IC Liquid Handling Set for PILS Peristaltic Pump, 8 Channel KNF Vacuum Pump for Saturated Vapors Model No. N840.3FT.40P Multi-Channel Annular Denuders URG Model No. URG x242-4CSS PM 2.5 Cyclone URG Model No. URG EH MagIC Net TM 2.4 Professional Metrosep A Supp 5-150/ Metrosep A Supp 4/5 Guard column Metrosep C Metrosep C 4 Guard * to be ordered at KNF ** to be ordered at URG * ** ** The Particle Into Liquid Sampler, known as PILS, is able to transfer airborne particles into the aqueous phase. In the mixing chamber of the PILS supersaturated water steam condenses on the aerosol particles. These grow in size and are finally collected by impaction. A carrier liquid containing lithium bromide as internal standard transfers the collected sample via a de-bubbler into the Ionchromatography system for the determination of anions and cations. Page 1 of 9

2 Sample Continuous collection of outdoor aerosols with a cut off of 2.5 μm at Gladesville NSW, 9km North West from Sydney CBD. Prior to the aerosol collection, acid gases are removed by a denuder coated with sodium carbonate and alkaline gases are removed by a denuder coated with citric acid. Analysis Samples are transferred continuously to the injection loop for the analysis by using a multichannel peristaltic pump. The loops are put back to the fill position right after the injection. In this way the loop is flushed during the chromatogram run time and ready for the next injection. Calculation Automatic integration with MagIC Net 2.4 software, using peak area for all the analytes. Air concentrations were directly calculated by the software as user-defined results. Standards Standards were all spiked with 920 ppb bromide and 80 ppb lithium as internal standard for calibration. The internal standard is used to compensate for the dilution of the carrier liquid by the condensated steam from the aerosols. Anion Chloride Nitrite Nitrate Sulphate Std. 1 [μg/l] Std. 2 [μg/l] Std. 3 [μg/l] Std. 4 [μg/l] Std. 5 [μg/l] Cation Sodium Ammonium Potassium Calcium Magnesium Std. 1 [μg/l] Std. 2 [μg/l] Std. 3 [μg/l] Std. 4 [μg/l] Std. 5 [μg/l] IC Reagents: (In ultra-pure water, resistivity > 18 MOhm * cm (25 C)) Anion Eluent: mmol/l sodium carbonate mmol/l sodium hydrogen carbonate IC Suppressor solutions: - 50 mmol sulphuric acid - Ultrapure water Cation Eluent: mmol/l nitric acid mmol/l dipicolinic acid Method Description The coating solutions for the denuders are: - For acid gases: Mix 50 ml of ultrapure water with 50 ml of ethanol. Add 1 g glycerol and 1 g sodium carbonate. - For basic gases: 0.5 g citric acid is added to 50 ml of ethanol. After that 0.5 ml of glycerol is added. The denuders are coated by applying 10 ml of coating solution. After distributing it evenly on the denuder the coating solution is removed. The denuders are finally dried with a clean air flow of 2-3 L/min. For this application the Inline Eluent Preparation was used. Inline Eluent Preparation was setup according to AW CH in a separate workplace. The cations Inline Eluent Preparation method of AW CH was integrated in the PILS AnCat method used in this application work. The Anion and Cation system was linked in series from the de-bubbler of the PILS. For the calculation of the air concentration the flow of the carrier liquid with internal standard Fcarrier was measured, with a result of 0.4 ml/min. The air flow Fair through the PILS is 16.7 L/min. 1 M 3 / Hour) With the concentration of the analyte cliquid (μg/l) in the liquid, containing the compensated steam and aerosols (corrected for the dilution by the internal standard) the air concentration cair (μg/m3) is calculated as follows: cair = cliquid * Fcarrier / Fair Page 2 of 9

3 IC Parameters Anion Channel Eluent Flow 0.7 ml/min Column temperature 30 C Sample loop 250 μl MSM Regenerant 100 mmol/l Sulfuric acid MSM Rinsing water Carbonate Suppressor ON Cation Channel Eluent Flow 0.9 ml/min Column temperature 30 C Sample loop 250 μl PILS Parameters Air flow 16.7L/min Internal Carrier Flow 0.4 ml/min Steamer Temperature 165 C Cylcone 2.5 μm Sampler (PILS) for ground and airborne measurements of water soluble aerosol composition, Atmos. Environ. 37, (2003). (3) C. Emmenegger, R. Jansen and M. Laeubli, Determination of anions and cations in aerosols, Pittcon 2008, (search for EN). (4) R.E. Peltier, A.H. Hecobian, R.J. Weber, A. Stohl., E.L. Atlas, D.D. Riemer, D.R. Blake, E. Apel, T. Campos and T. Karl, Atmos. Chem. Phys. Discuss. 7, (2007). (5) Forster, P. et al. in Climate Change 2007: The Physical Science Basis (eds Solomon, S. et al.) (Cambridge Univ. Press, 2007). (6) Nature Geoscience 6, (2013) doi: /ngeo1800 Author Bart Cleeren Product Manager Ion Chromatography Metrohm Australia - MEP Instruments Calculation Automatic integration with MagIC Net 2.4 software, using peak area for all analytes. Sample Results Appendix 1: Instrumentation setup, calibration curves, chromatograms Appendix 2: Aerosol monitoring and weather conditions in Sydney Date: Thursday, July 18, 2013 Reference (1) R.J. Weber, D.A. Orsini, Y. Daun, Y.-N. Lee, P.J. Klotz and F. Brechtel, A Particle-Into-Liquid Collector for rapid measurement of aerosol bulk chemical composition, Aerosol Sci. Technol. 35, (2001). (2) D.A. Orsini, Y. Ma, A. Sullivan, B. Sierau, K. Baumann and R.J. Weber, Refinements to the Particle-Into-Liquid- Page 3 of 9

4 Appendix 1: Instrumentation setup, calibration curves, chromatograms Instrumentation setup Page 4 of 9

5 Typical anion chromatogram Typical cation chromatogram Page 5 of 9

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9 Appendix 2: Aerosol monitoring and weather conditions in Sydney Morning traffic Diesel trucks running idle close to air aspiration Conversion NO 2 to NO 3 Page 9 of 9

Anion chromatography using on-line recycled eluents

Journal of Chromatography A, 1089 (2005) 82 86 Anion chromatography using on-line recycled eluents Takashi Yokoyama, Hitoe Maekubo, Asami Sakai, Michio Zenki Department of Chemistry, Faculty of Science,