Crystallization of Pentaerythritol I. Solubility, Density and Metastable Zone Width

1994 ◽  
Vol 59 (6) ◽  
pp. 1261-1269 ◽  
Author(s):  
Miloslav Karel ◽  
Jaroslav Nývlt ◽  
Angelo Chianese

Solubility of pentaerythritol in water has been determined using literature data, the polythermal method and the dry residue method. Densities of its aqueous solutions have been measured using a pycnometer. Kinetics of crystallization of the pentaerythritol has been determined in laboratory experiments. In this paper, metastable zone width measurements have been employed for the assessment of the primary nucleation rate.

2015 ◽  
Vol 49 (6) ◽  
pp. 869-876 ◽  
Author(s):  
Guisheng Zeng ◽  
Hui Li ◽  
Sheng Huang ◽  
Xianyong Wang ◽  
Junhong Chen

1984 ◽  
Vol 49 (3) ◽  
pp. 559-569 ◽  
Author(s):  
Jaroslav Nývlt

The metastable zone width of an aqueous solution of KCI was measured as a function of the time and temperature of overheating above the equilibrium solubility temperature. It has been found that when the experiments follow close upon one another, the parameters of the preceding experiment affect the results of the experiment to follow.The results are interpreted in terms of hypotheses advanced in the literature to account for the effect of thermal history of solution. The plausibility and applicability of these hypotheses are assessed for the given cause of aqueous solution of a well soluble electrolyte.


2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Abdelali Borji ◽  
Fatima-Ezzahra Borji ◽  
Abdelaziz Jourani

Using the spectrophotometric method, as a new method, the influence of dextran on the sucrose solubility and metastable zone width has been studied. In agreement with the literature the experimental data show that the dextran has a negligible effect on the sucrose solubility. The results also show that this impurity decreases the sucrose metastable zone width. The study of the nucleation kinetics performed, using Nyvlt’s approach, shows that the dextran accelerates the nucleation and that the nuclei are formed in the solution by instantaneous nucleation. The presence of dextran in the system causes a decrease in the growth rate of sucrose. The growth process of sucrose is governed by a Birth and Spread mechanism. The kinetic parameters of sucrose growth in aqueous solutions without and with dextran were estimated.


1970 ◽  
Vol 6 (2) ◽  
pp. 151-162 ◽  
Author(s):  
Jaroslav Nývlt ◽  
Rudolf Rychlý ◽  
Jaroslav Gottfried ◽  
Jiřina Wurzelová

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Abdur Rashid ◽  
Edward T. White ◽  
Tony Howes ◽  
James D. Litster ◽  
Ivan Marziano

To investigate the crystallization of ibuprofen [((RS)-2-(4-(2-methylpropyl) phenyl) propanoic acid)] from ethanol and water-ethanol mixtures it is necessary to know the nucleation limits of its solutions. In the absence of crystals, nucleation will seldom occur below the PNT (primary nucleation threshold). If crystals are present, nucleation will seldom occur until below the lower SNT (secondary nucleation threshold). Below the SNT, crystals will still grow with negligible nucleation. PNT and SNT values (expressed as relative supersaturationσ) have been measured at 10, 25, and 40°C for ibuprofen in ethanol and in a range of mixtures of different ethanol (E)/water (W) ratios. The induction times were determined from observing the times to nucleate for a range of different supersaturated solutions at a given temperature andE/Wratio. As expected, lowering the supersaturation leads to longer induction times. In ethanol, the SNT values are small and thus the secondary metastable zone width (MSZW) is relatively narrow with a 1 h SNT relative supersaturation typically aboutσ~ 0.05. The 1 h PNT values are much larger with values forσaround 0.3. In aqueous ethanolic mixtures at 25°C, both the PNT and SNT decrease as the water content increases.


2011 ◽  
Vol 198 (8) ◽  
pp. 1004-1017 ◽  
Author(s):  
Johanne Bonnin-Paris ◽  
Stéphane Bostyn ◽  
Jean-Louis Havet ◽  
Henri Fauduet

CrystEngComm ◽  
2013 ◽  
Vol 15 (36) ◽  
pp. 7285 ◽  
Author(s):  
Fredrik L. Nordström ◽  
Michael Svärd ◽  
Åke C. Rasmuson

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