Effect of Sodium Sulfate on Nucleation Behavior and the Crystal Morphology of Taurine

Abstract

Two theoretical methods, self‐consistent Nývlt‐like approach and Sangwal's classical 3D nucleation theory‐based method, are employed to analyze the effects of additives (sodium sulfate) on the nucleation behavior of taurine. By correlating the measured metastable zone width of taurine containing different sodium sulfate concentrations, with saturation temperature and cooling rate, nucleation kinetic parameters in both two methods are determined. Fitting results demonstrate that higher sodium sulfate concentration results in the increase of solid–liquid interfacial energy γ, contrarily higher saturation temperature has the opposite effect thus changing of nucleation rate. The molecular modeling techniques are then applied to investigate the changes in the morphology of taurine which caused by the presence of sodium sulfate. Through molecular dynamic simulations, the interaction energy of sodium sulfate with taurine crystal faces are obviously larger than those of taurine and these differences on the (011) and (11‐1) are more significant than those on (021) and (111) faces. As a result, the growth of (011) and (11‐1) faces is inhibited and the morphology of taurine crystal is modified from needle to columnar. The influence of sodium sulfate on taurine studied in this work provides theoretical guidance for industrial production.

New Salts and Cocrystals of Pymetrozine with Improvements on Solubility and Humidity Stability: Experimental and Theoretical Study

“…PMZ-2,6HBA was the exceptional one, for its solubility was 0.1847 g/L, the lowest among all the crystals. With the Morphology module of Materials Studio 6.0, the theoretical morphology and the main crystal faces of seven new crystals and PMZ•2H 2 O were calculated by the attachment energy (AE) approach, 67 as shown in Figure S15. In PMZ-2,6HBA, neither of the main crystal faces exposed the hydrophilic groups such as hydroxyl groups, carboxyl groups, and amino groups.…”

Multicomponent Crystals of Clozapine with Improved Solubility: A Combined Theoretical and Experimental Strategy on Coformer Screening and Structure–Property

“…CLZ-FA1 is a special case, having the lowest solubility of 0.0007963 g/g (47 times) among all crystals. The crystal morphology simulations and major crystal surfaces of eight multicomponent crystals were calculated for eight crystals by the attachment energy (AE) model 84 through the Morphology module of Materials Studio 6.0(Accelrys, USA), as shown in Figure S16. For CLZ-FA1, there is only one amino group on its main crystalline surface, and no other hydrophilic groups such as hydroxyl and carboxyl groups; as for CLZ-CA, its main crystalline surfaces expose more hydrophilic groups such as hydroxyl and carboxyl groups.…”

Effect of process impurities on crystallization thermodynamics and nucleation kinetics of taurine

“…As a non‐protein amino acid, taurine (2‐aminoethanesulfonic acid, C 2 H 7 NO 3 S, CAS number: 107‐35‐7) is widely used as a nutritional supplement and biochemical reagent and so on, 1,2 which can improve visual function and affect sugar metabolism. In the well‐established preparation route of taurine, the crystallization process is often the core step that directly affects products quality 3,4 . Taurine synthesis route from ethylene oxide (see Figure 1) became the most competitive route due to its environmental friendliness and high efficiency in recent years 5 .…”

“…Nucleation occurs when the cooling system reaches to the metastable zone boundary and enters the unstable zone. Investigation on MSZW contributes to the understanding of nucleation behavior, crystal growth and crystal size modulation 4,13 . Since 1968, various deterministic theoretical models of primary nucleation have been developed to predict MSZW of different systems 14 .…”

“…In the wellestablished preparation route of taurine, the crystallization process is often the core step that directly affects products quality. 3,4 Taurine synthesis route from ethylene oxide (see Figure 1) became the most competitive route due to its environmental friendliness and high efficiency in recent years. 5 The raw material SI and by-product SA can enter the taurine crystallization process and their influence on crystallization thermodynamics remains unclear.…”