Zhao, Y, Yao, J and Wang, M (2016) On-line monitoring of the crystallization process: relationship between crystal size and electrical impedance spectra. Measurement Science and Technology, 27 (7). 074007. ISSN 0957-0233
Abstract
On-line monitoring of crystal size in the crystallization process is crucial to many pharmaceutical and fine-chemical industrial applications. In this paper, a novel method is proposed for the on-line monitoring of the cooling crystallization process of L-glutamic acid (LGA) using electrical impedance spectroscopy (EIS). The EIS method can be used to monitor the growth of crystal particles relying on the presence of an electrical double layer on the charged particle surface and the polarization of double layer under the excitation of alternating electrical field. The electrical impedance spectra and crystal size were measured on-line simultaneously by an impedance analyzer and focused beam reflectance measurement (FBRM), respectively. The impedance spectra were analyzed using the equivalent circuit model and the equivalent circuit elements in the model can be obtained by fitting the experimental data. Two equivalent circuit elements, including capacitance (C 2) and resistance (R 2) from the dielectric polarization of the LGA solution and crystal particle/solution interface, are in relation with the crystal size. The mathematical relationship between the crystal size and the equivalent circuit elements can be obtained by a non-linear fitting method. The function can be used to predict the change of crystal size during the crystallization process.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2016 IOP Publishing Ltd. This is an author produced version of a paper published in Measurement Science and Technology. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | electrical impedance spectroscopy, crystallization, particle size, on-line, equivalent circuit model |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) > Institute for Particle Science and Engineering (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 06 May 2016 12:49 |
Last Modified: | 01 Jul 2017 07:04 |
Published Version: | http://dx.doi.org/10.1088/0957-0233/27/7/074007 |
Status: | Published |
Publisher: | IOP Publishing |
Identification Number: | 10.1088/0957-0233/27/7/074007 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:99361 |