AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
A Nanoparticle Nebulizer for Generation of Aerosolized Colloid Particles with Reduced Interference from Non-Volatile Residue
DEREK OBERREIT, Gary Van Schooneveld, David Blackford, Fluid Measurement Technologies, Inc.
Abstract Number: 621 Working Group: Instrumentation and Methods
Abstract Dispersion of colloid nanoparticles into an aerosol first requires nebulization of the colloid into fine droplets and subsequent evaporation of the solvent from them. Following solvent evaporation, droplets that did not contain a colloid particle form particles composed of non-volatile solvent residue. Droplets that do contain colloid particles result in aerosolized colloid particles with a coating of non-volatile residue. To reduce the interference by non-volatile residue particles as well as effect on the colloid particle properties (surface chemistry, size), it is desirable to create droplets containing a low volume of solvent. This is especially true for aerosolization of nanoparticles that approach the size of the non-volatile residue particles. Nebulization is typically accomplished using either pneumatic or electrospray methods. While electrospray methods do provide sufficiently small droplets (~0.3 μm), there are several limitations to the method including poor long term stability and necessity for a conductive solvent. Common pneumatic nebulizers create droplet distributions with a peak diameter near 2.0 μm which leads to a significant amount of non-volatile residue interference in the aerosol. We present a new commercially available pneumatic nebulizer that is designed to produce a high number concentration of small droplets with a peak diameter less than 0.5 μm. We compare the performance of this nebulizer with existing aerosolization methods for a variety of colloids. We also show additional applications of this device for monitoring colloid concentrations in dilute systems such as ultrapure water systems and in liquid filter efficiency testing.