Nucleation control and separation of vanillin polymorphs I and II through the swift cooling crystallization process

Abstract

Stable form-I and metastable form-II polymorphs of vanillin are identified through morphology and separated in terms of supersaturation ranges from pure aqueous solution without the use of nucleation selecting materials.

Mesoscale clusters of organic solutes in solution and their role in crystal nucleation

“…3 However, crystallization of organic molecular compounds is of importance in many other branches of fine-and specialty chemical industry, e.g. in the food industry, 4 and for production of pigments and dyes. 5 Despite a long history of extensive research, the present level of understanding of the thermodynamics, kinetics and mechanisms responsible for primary nucleation is limited.…”

“…3 However, crystallization of organic molecular compounds is of importance in many other branches of fine- and specialty chemical industry, e.g. in the food industry, 4 and for production of pigments and dyes. 5…”

Polymorph and Morphology Formation of Cerium Carbonate from Reactive Crystallization

“…More applications and new functional materials might emerge if morphology-controlled crystals could be achieved. Supersaturation, temperature, solvent, and many other factors have been found to have direct relationships with the formation of different polymorphs and crystal morphology during solution crystallization. − When it comes to reactive crystallization, the polymorph formation and the control of the crystal morphology seem to be more complicated due to the fact that the overall pathway involves chemical reaction, crystal nucleation and growth, and the subtle interaction between the thermodynamics and kinetics should also be considered carefully …”

Ethyl Vanillin Rapid Crystallization from Carboxymethyl Chitosan Ion-Switchable Hydrogels

“…As early as 1991, Singh et al [ 9 ] found that Van/EVA crystals were polymorphic with conventional type I and type Ⅱ crystallized from chloroform-carbon tetrachloride solution but type Ⅲ and type Ⅳ only discovered from molten state. Subsequently, many researchers have developed various techniques to grow Van or EVA crystal in water [ 10 ], methanol and ethanol [ 11 ], methanol-chloroform co-solvent [ 8 ], oil-extrusion method [ 12 ], nickel foam template [ 13 ] and vapor diffusion crystallization [ 14 ]. These methods are effective and suitable for use but involve inevitable shortcomings of long duration, using organic solvents, of being low quality, or needing sophisticated equipment.…”