Optical properties of selected components of mineral dust aerosol processed with organic acids and humic material

Visible light scattering phase function and linear polarization profiles of mineral dust components processed with organic acids and humic material are measured, and results are compared to T-matrix simulations of the scattering properties. Processed samples include quartz mixed with humic material, and calcite reacted with acetic and oxalic acids. Clear differences in light scattering properties are observed for all three processed samples when compared to the unprocessed dust or organic salt products. Results for quartz processed with humic acid sodium salt (NaHA) indicate the presence of both internally mixed quartz-NaHA particles and externally mixed NaHA aerosol. Simulations of light scattering suggest that the processed quartz particles become more moderate in shape due to the formation of a coating of humic material over the mineral core. Experimental results for calcite reacted with acetic acid are consistent with an external mixture of calcite and the reaction product, calcium acetate. Modeling of the light scattering properties does not require any significant change to the calcite particle shape distribution although morphology changes cannot be ruled out by our data. It is expected that calcite reacted with oxalic acid will produce internally mixed particles of calcite and calcium oxalate due to the low solubility of the product salt. However, simulations of the scattering for the calcite-oxalic acid system result in rather poor fits to the data when compared to the other samples. The poor fit provides a less accurate picture of the impact of processing in the calcite-oxalic acid system.

[1]  M. Gilles,et al.  Organic Aerosol Growth Mechanisms and Their Climate-Forcing Implications , 2004, Science.

[2]  Vicki H. Grassian,et al.  A combined laboratory and modeling study of the infrared extinction and visible light scattering properties of mineral dust aerosol , 2013 .

[3]  Xin Yang,et al.  Single particle mass spectrometry of oxalic acid in ambient aerosols in Shanghai: Mixing state and formation mechanism , 2009 .

[4]  V. Grassian.  Heterogeneous uptake and reaction of nitrogen oxides and volatile organic compounds on the surface of atmospheric particles including oxides, carbonates, soot and mineral dust: Implications for the chemical balance of the troposphere , 2001 .

[5]  Erratum to “Heterogeneous chemistry of individual mineral dust particles from different dust source regions: the importance of particle mineralogy”: [Atmos. Environ. 38 (36) (2004) 6253–6261] , 2005 .

[6]  P. Formenti,et al.  Chemistry of rain events in West Africa: evidence of dust and biogenic influence in convective systems , 2010 .

[7]  Weijun Li,et al.  Observation of nitrate coatings on atmospheric mineral dust particles , 2008 .

[8]  Jennifer D. Schuttlefield,et al.  Water adsorption and cloud condensation nuclei activity of calcite and calcite coated with model humic and fulvic acids , 2008 .

[9]  M. Tolbert,et al.  Optical properties of internally mixed aerosol particles composed of dicarboxylic acids and ammonium sulfate. , 2009, The journal of physical chemistry. A.

[10]  P. Formenti,et al.  Mapping the physico-chemical properties of mineral dust in western Africa: mineralogical composition , 2014 .

[11]  V. Grassian,et al.  Correlated IR spectroscopy and visible light scattering measurements of mineral dust aerosol , 2010 .

[12]  S. Paulson,et al.  Genetic Algorithm Inversion of Dual Polarization Polar Nephelometer Data to Determine Aerosol Refractive Index , 2007 .

[13]  J. Hovenier,et al.  The IAA cosmic dust laboratory: Experimental scattering matrices of clay particles , 2011 .

[14]  David M. Cwiertny,et al.  Chemistry and photochemistry of mineral dust aerosol. , 2008, Annual review of physical chemistry.

[15]  Martin Ebert,et al.  Recent progress in understanding physical and chemical properties of African and Asian mineral dust , 2011 .

[16]  Hester Volten,et al.  Scattering matrix of large Saharan dust particles: Experiments and computations , 2007 .

[17]  Larry D. Travis,et al.  Capabilities and limitations of a current FORTRAN implementation of the T-matrix method for randomly oriented, rotationally symmetric scatterers , 1998 .

[18]  G. Zhuang,et al.  Characteristics and sources of formic；acetic and oxalic acids in PM2.5 and PM10 aerosols in Beijing；China , 2007 .

[19]  V. Grassian,et al.  Simultaneous measurement of light-scattering properties and particle size distribution for aerosols : Application to ammonium sulfate and quartz aerosol particles , 2007 .

[20]  M. Kahnert,et al.  Modelling light scattering by mineral dust using spheroids : assessment of applicability , 2011 .

[21]  J. Arriaga-Colina,et al.  Observations of formic and acetic acids at three sites of Mexico City. , 2002, The Science of the total environment.

[22]  M. Kahnert,et al.  Can particle shape information be retrieved from light-scattering observations using spheroidal model particles? , 2011 .

[23]  J. Duran,et al.  Interfacial and rheological properties of humic acid/hematite suspensions. , 2003, Journal of colloid and interface science.

[24]  V. Grassian,et al.  Laboratory study of the effect of oxalic acid on the cloud condensation nuclei activity of mineral dust aerosol , 2012 .

[25]  Hester Volten,et al.  Scattering matrices of mineral aerosol particles at 441.6 nm and 632.8 nm , 2001 .

[26]  V. Grassian,et al.  Infrared extinction spectroscopy and micro‐Raman spectroscopy of select components of mineral dust mixed with organic compounds , 2013 .

[27]  G. H. Nancollas,et al.  Kinetics of crystal growth of calcium oxalate monohydrate , 1974 .

[28]  P. Buseck,et al.  Sulfate-coated dust particles in the free troposphere over Japan , 2006 .

[29]  H. S. Fogler,et al.  The kinetics of calcite dissolution in acetic acid solutions , 1998 .

[30]  Y. Rudich,et al.  Adsorption of organic compounds pertinent to urban environments onto mineral dust particles , 2004 .

[31]  Y. Rudich,et al.  Changes in the optical properties of benzo[a]pyrene-coated aerosols upon heterogeneous reactions with NO2 and NO3. , 2011, Physical chemistry chemical physics : PCCP.

[32]  A. Ravishankara,et al.  Parameterization for the relative humidity dependence of light extinction: Organic-ammonium sulfate aerosol , 2007 .

[33]  K. Prather,et al.  Investigations of the diurnal cycle and mixing state of oxalic acid in individual particles in Asian aerosol outflow. , 2007, Environmental science & technology.

[34]  V. Grassian,et al.  A Newly Designed and Constructed Instrument for Coupled Infrared Extinction and Size Distribution Measurements of Aerosols , 2007 .

[35]  K. Prather,et al.  Direct observations of the atmospheric processing of Asian mineral dust , 2006 .

[36]  V. Grassian,et al.  Heterogeneous conversion of calcite aerosol by nitric acid. , 2007, Physical chemistry chemical physics : PCCP.

[37]  A. Laskin,et al.  Heterogeneous chemistry of individual mineral dust particles from different dust source regions: the importance of particle mineralogy , 2004 .

[38]  V. Grassian,et al.  Reactive uptake of acetic acid on calcite and nitric acid reacted calcite aerosol in an environmental reaction chamber. , 2008, Physical chemistry chemical physics : PCCP.

[39]  D. Murphy,et al.  Chemical components of single particles measured with Particle Analysis by Laser Mass Spectrometry (PALMS) during the Atlanta SuperSite Project: Focus on organic/sulfate, lead, soot, and mineral particles , 2002 .

[40]  S. Takahama,et al.  Coatings and clusters of carboxylic acids in carbon-containing atmospheric particles from spectromicroscopy and their implications for cloud-nucleating and optical properties , 2010 .

[41]  A. Laskin,et al.  Heterogeneous chemistry of individual mineral dust particles with nitric acid: A combined CCSEM/EDX, ESEM, and ICP‐MS study , 2005 .

[42]  Bin Chen,et al.  Morphological and chemical modification of mineral dust: Observational insight into the heterogeneous uptake of acidic gases , 2005 .