Degree Type

Dissertation

Date of Award

1999

Degree Name

Doctor of Philosophy

Department

Chemical and Biological Engineering

First Advisor

Maurice A. Larson

Abstract

The growth rates of secondary crystal nuclei determine the number of crystals that will reach a size large enough to contribute to the final product mass in a crystallization process. Contact nuclei were chosen for study because crystals nucleated under conditions of low supersaturation are formed by contact or secondary nucleation. High supersaturation levels are required for primary nucleation to occur. Growth rate dispersion complicates the prediction of growth rates and product size distributions. Having growth rate dispersion in a crystallizing system means that despite the population of crystals having all been nucleated and grown under identical conditions, they grow at different rates. To predict and control crystallizer behavior, one must be able to characterize growth rates and growth rate dispersion as a function of the supersaturation conditions in the crystallizer. This dissertation uses single crystal growth experiments to characterize the growth rate dispersion of secondary nuclei as a function of supersaturation. In addition, growth rates and growth rate dispersion are related to integral strain and dislocation density, two factors known to affect crystal growth rates.

DOI

https://doi.org/10.31274/rtd-180813-13840

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

Christopher Michael Jones

Language

en

Proquest ID

AAI9924727

File Format

application/pdf

File Size

103 pages

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