Time-Resolved Measurements of the Evaporation of Volatile Components from Single Aerosol Droplets

A strategy for examining the dynamic hygroscopic response of single aerosol particles is reported, allowing a direct investigation of the interplay of thermodynamic and kinetic factors regulating the time dependence of particle size. In particular, we investigate the rapid evaporation of water from water–glycerol droplets, measuring the evolving size with a time resolution of <10 ms (with as low as 2.5 ms being possible) over a time range from subsecond to many hours. Measurements can be made on sequential droplets generated from a droplet-on-demand generator, and a reproducibility of better than ±0.25 μm in droplet size over tens of events can be achieved at any resolved time point considered during an evaporation process lasting >2 s. The time-dependent measurements of evolving droplet size are compared with an analytical treatment of the evaporation process. Excellent agreement between measurements and simulations is found over a wide range of starting droplet compositions. The benefits of using this approach for investigating water transport within the bulk of an aerosol particle or to/from the droplet surface are discussed. Copyright 2012 American Association for Aerosol Research

[1]  J. Gentry,et al.  Spray Drying Drop Morphology: Experimental Study , 2003 .

[2]  Zhiqiang Gao,et al.  Resonance-based light scattering techniques for investigation of microdroplet processes. , 2008, Faraday discussions.

[3]  Peter Brimblecombe,et al.  Thermodynamic modelling of aqueous aerosols containing electrolytes and dissolved organic compounds , 2001 .

[4]  Chak K. Chan,et al.  Study of the Hygroscopic Properties of Selected Pharmaceutical Aerosols Using Single Particle Levitation , 2000, Pharmaceutical Research.

[5]  L. F. Phillips,et al.  Onsager heat of transport for water vapour at the surface of glycerol–water mixtures , 2006 .

[6]  J. Mønster,et al.  Evaporation of methyl- and dimethyl-substituted malonic, succinic, glutaric and adipic acid particles at ambient temperatures , 2004 .

[7]  S. Bakhoum,et al.  Study of chemistry in droplets with net charge before and after Coulomb explosion: ion-induced nucleation in solution and implications for ion production in an electrospray. , 2005, Analytical chemistry.

[8]  S. Ghan,et al.  Kinetic limitations on cloud droplet formation and impact on cloud albedo , 2001 .

[9]  E. James Davis,et al.  Microparticle raman spectroscopy of multicomponent aerosols , 1991 .

[10]  R. Charlson,et al.  The effects of atmospheric organics on aqueous droplet evaporation , 1997 .

[11]  E. Davis,et al.  Single aerosol particle size and mass measurements using an electrodynamic balance , 1980 .

[12]  T. Allen,et al.  Measurement of droplet interfacial phenomena by light‐scattering techniques , 1988 .

[13]  W. L. Badger,et al.  Vapor Pressures of Glycerol-Water and Glycerol-Water-Sodium Chloride Systems , 1925 .

[14]  G. Lavergne,et al.  Temperature measurements of binary droplets using three-color laser-induced fluorescence , 2006 .

[15]  Timo Vesala,et al.  Commentary on cloud modelling and the mass accommodation coefficient of water , 2005 .

[16]  E. Davis,et al.  MASS TRANSFER FROM A SINGLE MICRO-DROPLET TO A GAS FLOWING AT LOW REYNOLDS NUMBER , 1987 .

[17]  Laura Mitchem,et al.  Measurements of mass and heat transfer at a liquid water surface during condensation or evaporation of a subnanometer thickness layer of water. , 2010, Physical review letters.

[18]  G. Mie.  Beiträge zur Optik trüber Medien, speziell kolloidaler Metallösungen , 1908 .

[19]  Heiko K. Cammenga,et al.  Vapor pressure and evaporation coefficient of glycerol , 1977 .

[20]  Michael D. Barnes,et al.  A CCD BASED APPROACH TO HIGH-PRECISION SIZE AND REFRACTIVE INDEX DETERMINATION OF LEVITATED MICRODROPLETS USING FRAUNHOFER DIFFRACTION , 1997 .

[21]  S. H. Chen,et al.  Light scattering from water droplets in the geometrical optics approximation. , 1981, Applied optics.

[22]  B. Weigand,et al.  Composition measurements of binary mixture droplets by rainbow refractometry. , 2007, Applied optics.

[23]  Suresh K. Aggarwal,et al.  A REVIEW OF SPRAY IGNITION PHENOMENON , 1997 .

[24]  M. Bogan,et al.  Promotion of α-cyano-4-hydroxycinnamic acid and peptide cocrystallization within levitated droplets with net charge , 2005, Journal of the American Society for Mass Spectrometry.

[25]  J. Reid,et al.  Probing the evaporation of ternary ethanol-methanol-water droplets by cavity enhanced Raman scattering. , 2007, Physical chemistry chemical physics : PCCP.

[26]  J. Reid,et al.  A comparative study of the mass and heat transfer dynamics of evaporating ethanol/water, methanol/water, and 1-propanol/water aerosol droplets. , 2006, The journal of physical chemistry. B.

[27]  R Anthony Cox,et al.  Studies of single aerosol particles containing malonic acid, glutaric acid, and their mixtures with sodium chloride. I. Hygroscopic growth. , 2010, The journal of physical chemistry. A.

[28]  E. James Davis,et al.  A History of Single Aerosol Particle Levitation , 1997 .

[29]  G. Brenn,et al.  Drying of acoustically levitated droplets of liquid–solid suspensions: Evaporation and crust formation , 2002 .

[30]  T. G. Cowling,et al.  The mathematical theory of non-uniform gases : an account of the kinetic theory of viscosity, thermal conduction, and diffusion in gases , 1954 .

[31]  T. Leisner,et al.  Charge induced stability of water droplets in subsaturated environment , 2010 .

[32]  C. Tropea,et al.  Evaporation of pure liquid droplets: Comparison of droplet evaporation in an acoustic field versus glass-filament , 2011 .

[33]  J. Reid,et al.  Evaporation of ethanol/water droplets: examining the temporal evolution of droplet size, composition and temperature. , 2005, The journal of physical chemistry. A.

[34]  A. Wexler,et al.  Atmospheric aerosol models for systems including the ions H+, NH4+, Na+, SO42−, NO3−, Cl−, Br−, and H2O , 2002 .

[35]  A. Wexler,et al.  Thermodynamic Model of the System H+−NH4+−Na+−SO42-−NO3-−Cl-−H2O at 298.15 K , 1998 .

[36]  Jonathan P. Reid,et al.  Measurements of the timescales for the mass transfer of water in glassy aerosol at low relative humidity and ambient temperature , 2011 .

[37]  J. Reid,et al.  Temperature measurement of single evaporating water droplets in a nitrogen flow using spontaneous Raman scattering. , 2009, Physical chemistry chemical physics : PCCP.

[38]  G. Schweiger,et al.  Linear Raman Spectroscopy on Droplet Chains: A New Experimental Method for the Analysis of Fast Transport Processes and Reactions on Microparticles , 1995 .

[39]  Sigurd Bauerecker,et al.  Generation and characterization of surface layers on acoustically levitated drops. , 2007, Journal of colloid and interface science.

[40]  I. Riipinen,et al.  Evaporation of multicomponent droplets. , 2007 .

[41]  S. Aggarwal.  A review of spray ignition phenomena: Present status and future research , 1998 .

[42]  R. A. Cox,et al.  Studies of single aerosol particles containing malonic acid, glutaric acid, and their mixtures with sodium chloride. II. Liquid-state vapor pressures of the acids. , 2010, The journal of physical chemistry. A.

[43]  Ozonolysis of maleic acid aerosols: effect upon aerosol hygroscopicity, phase and mass. , 2010, Environmental science & technology.

[44]  E. Davis.  Transport Phenomena with Single Aerosol Particles , 1982 .

[45]  C. Brinker,et al.  Numerical Simulation of Ethanol-Water-NaCl Droplet Evaporation. , 2010 .

[46]  James W. Davis,et al.  Multicomponent evaporation of single aerosol droplets , 1982 .

[47]  C. Brinker,et al.  Measurements and simulations of the near-surface composition of evaporating ethanol-water droplets. , 2009, Physical Chemistry, Chemical Physics - PCCP.

[48]  C. Chan,et al.  Hygroscopicity of water-soluble organic compounds in atmospheric aerosols: amino acids and biomass burning derived organic species. , 2005, Environmental science & technology.

[49]  Time integrated detection of femtosecond laser pulses scattered by small droplets. , 2008, Applied optics.

[50]  M. Kulmala,et al.  An analytical expression for the rate of binary condensational particle growth , 1993, Proceedings of the Royal Society of London. Series A: Mathematical and Physical Sciences.