Crystal growth rate parameters from isothermal desupersaturation experiments

Yanfeng Qiu, Åke C. Rasmuson, Richard Cotterell

Research output: Contribution to journalArticlepeer-review

Abstract

The determination of two-step crystal growth rate parameters by isothermal desupersaturation experiments relies upon the adequate use of experimental data. The growth rate vs supersaturation relation is always almost linear on a log-log diagram over a reasonable range of supersaturation, regardless of the mechanisms involved. Only within the slight curvature of the graph can we find the information available to separate the volume diffusion resistance from the surface integration resistance. Although different polynomials fit desupersaturation data well, significant differences occur in evaluated growth rates. Using a polynomial to correlate the desupersaturation data actually destroys essential information and, due to significant end effects, the range over which reliable growth rates may be obtained is reduced. Direct estimation of growth rate parameters by fitting the supersaturation balance equation to the supersaturation measurements circumvents these deficiencies. Furthermore, the direct parameter estimation technique is less sensitive to random errors in supersaturation measurements.

Original languageEnglish
Pages (from-to)1659-1667
Number of pages9
JournalChemical Engineering Science
Volume46
Issue number7
DOIs
Publication statusPublished - 1991

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