Study on the Polymorphism and Caking Mechanism of Glycine
|Keywords||Glycine Polymorphs Crystal transition Caking|
Glycine is the most simple of the amino acid of a structure , a very broad field of applications . So far found three kinds of crystal form : α , β , and γ-type crystal has a glycine . Of glycine producing countries , but due to crystallization technical backwardness , not required to control the products polymorphs , α- product in the production of glycine are metastable products during storage and transport due to crystal transition easy caking is very inconvenient to use . In this paper, the problems in China 's glycine production on the crystallization conditions of the common α and γ polymorphs of glycine and its transformation mechanism system . , Its crystal structure was determined by X-ray single - crystal diffractometer , and the molecular packing of the crystals analyzed by a single crystal of the α and γ crystal form obtained in different solution environments glycine . X-ray powder diffraction measurement, the α and γ crystal type monocrystalline method determined by powder XRD patterns glycine mixed crystal of the α and γ crystal content . Using laser dynamic method the effects of α-type and γ-type glycine in the purified water, and contains a certain amount of NaOH , a solubility in the aqueous solution of NaCl . Van't-Hoff equation , and Grant equation for glycine in pure water solubility data of the association, the association of the two kinds of equations results were satisfactory. A crystal transition glycine thermodynamic analysis . DSC determination of the thermodynamic properties of the α and γ- glycine crystal transition and melting process . Glycine crystallization process of different polymorphs experiments explore the mechanism of crystallization of different polymorphs of glycine , while factors affect glycine crystal transition , and combined with glycine recrystallization and crystal transformation of glycine caking mechanism analysis . The glycine polymorph crystallization and the crystal type changes , determine the specific crystalline form of glycine crystallization process and the factors influencing the process of crystal transformation , for the realization of the the glycine polymorphs of control and avoid product storage and transport process crystal transition basis .