Abstract

In this work we studied glycine crystallization with two main objectives: (i) to get improved control of crystal growth and polymorphic selectivity of organic molecules; (ii) to achieve additional insights into the nucleation mechanisms of glycine polymorphs. To reach these goals, membrane crystallization technology, a tool which allows improved control of supersaturation in solution crystallization, was used under different operating conditions: the variable solvent removal rate, acidic and almost neutral pH, the presence of a pulsed electric field. The traditional explanation for the crystallization of a and g glycine polymorphs from aqueous solution is based on the general cyclic dimer hypothesis and the self-poisoning mechanism. In contrast with both the conventional theories, experimental results suggest that the relative nucleation rates with respect to the relative growth kinetics of the two forms under the different conditions play a dominant role in determining the polymorphic outcome. Our results instead support a molecular nucleation route where open chain dimers can behave as building units for both g- and a-glycines in the rate determining structuring step of the two-step nucleation mechanism.

Autore Pugliese

• Caliandro Rocco

Tutti gli autori

• G. Di Profio; M.T. Reijonen; R. Caliandro; A. Guagliardi; E. Curcio; E. Drioli

Titolo volume/Rivista

PCCP. Physical chemistry chemical physics

Anno di pubblicazione

2013

ISSN

1463-9076

ISBN

Non Disponibile

Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

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Numero di citazioni Scopus

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Ultimo Aggiornamento Citazioni

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Settori ERC

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Codici ASJC

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