As I mentioned prior to the 241st American Chemical Society (ACS) National Meeting and Exposition in Anaheim, there was an Enabling and Optimizing Chemical Reactions in Real Time Flow Chemistry and In Situ Analysis workshop. Continue reading
Regular visitors to this blog will be familiar with recent continuous flow chemistry events in what I consider to be a very exciting, fast-developing area of chemistry. When I was reading the recent blog post regarding the upcoming Pfizer Flow Technology Expo, I thought about other upcoming flow chemistry events, including: Continue reading
As 2010 comes to a close, I am taking one more opportunity to review the role that real-time in situ FTIR has played in advancing chemical research in academia on November 17. This online seminar is the sixth installment in the series: Recent Advances in Organic Chemistry Research in Academia Through the Use of Real-time In Situ FTIR. In preparing for this webinar, I have come realize how pervasive the use of in situ mid-IR is across a wide range of chemistry disciplines. For convenience sake, I focused only on the American Chemical Society (ACS) Journals research articles.
During the 2010 Fall American Chemical Society (ACS) meeting in Boston, Professor Steven V. Ley presented a novel approach to the use of flow chemistry as a synthetic technique. Continue reading
A paper by Jose Quevedo and Robert Pfeffer titled In Situ Measurements of Gas Fluidized Nanoagglomerates was just published on the web and will also be published in an upcoming issue of Industrial & Engineering Chemical Research.
The paper explores the in-process measurement of nanoparticle aggregates in a fluidized bed. Real-time, in-process particle system measurement with FBRM (Focused Beam Reflectance Measurement) and PVM (Particle Video Microscopy) show significant differences in the density and mean size of the aggregates formed in conventional fluid beds and microjet assisted fluid bed.
The authors report:
“Nanoparticles cannot be fluidized as individual particles but instead fluidize in the form of large (mean size about 100-400 μm), highly porous (internal porosity greater than 98%), hierarchical fractal structured agglomerates. Many nanopowders are very difficult to fluidize because of the large cohesive forces between the particles due to their very small size and high surface area…
In situ agglomerate size measurements and imaging of fluidized nanoagglomerates were achieved by reducing the electrostatic charge in the bed and using the FBRM and PVM probes from Lasentec.”
Electrostatic charges were reduced by bubbling the fluidizing gas through an alcohol-water mixture. This dramatically reduced adhesion of particles to surfaces and greatly improved the quality of the on-line measurements in this dry fluidized bed.
In Situ Measurements of Gas Fluidized Nanoagglomerates
Jose A. Quevedo† and Robert Pfeffer*‡
Otto York Department of Chemical, Biological and Pharmaceutical Engineering, New Jersey Institute of Technology, Newark, New Jersey 07102
Ind. Eng. Chem. Res., Article ASAP
Publication Date (Web): March 2, 2010
† Current address: Shell Global Solutions, P.O. Box 38000, 1030BN Amsterdam, The Netherlands.
‡ Current address: Department of Chemical Engineering, Arizona State University, Tempe, AZ 85287.
ReactIR Flow Cell: A New Analytical Tool for Continuous Flow Chemical Processing.
Catherine F. Carter†, Heiko Lange†, Steven V. Ley*†, Ian R. Baxendale†, Brian Wittkamp‡, Jon G. Goode§ and Nigel L. Gaunt§
† Innovative Technology Centre, University of Cambridge.
, ‡ Mettler-Toledo AutoChem, U.S.A.
, § Mettler-Toledo AutoChem, UK.
Org. Process Res. Dev., Article ASAP
Publication Date (Web): February 1, 2010
Copyright © 2010 American Chemical Society