Dissolution kinetics of crystalline alpha-glucose in 2-methyl 2-butanol

The purpose of the present study is the development of a kinetic model to predict and understand the dissolution of crystalline alpha-glucose in 2-methyl 2-butanol. The model takes into account three processes that might control the dissolution rate of alpha-glucose crystals. The first step, the detachment of alpha-glucose molecules from the solid surface at the solid-liquid interface, is characterised by k(R), the time-independent rate constant for interfacial reaction. The second step, the mass transport of alpha-glucose from the solid-liquid interface to the bulk solution across the boundary layer, is characterised by k(T)(L(t)), the rate constant for transport which depends on the particle size, L(t), and hence on time. The third step is the mutarotation of alpha-glucose in solution, characterised by the forward mutarotation kinetic constant, k(1). The constants k(R) and k(1), are obtained by fitting the model to the experimental data of alpha- and beta-glucose concentration in the bulk as a function of time. k(T)(L(t)) is estimated using correlations based on geometry, operational conditions and alpha-glucose particle size. The particle size distribution of the primary solid particles was experimentally determined. The model fits well the experimental results, and reveals that, for stirring speeds between 300 and 700 rpm, both transport and interfacial reaction share the control of the dissolution rate of alpha-glucose in 2-methyl 2-butanol

Solubility of glucose in mixtures containing 2-methyl-2- butanol, dimethyl sulfoxide, acids, esters, and water

Solubility measurements of glucose in a variety of binary, ternary, and multicomponent mixtures containing 2-methyl-2- butanol, dimethyl sulfoxide, acids, esters, and water at different temperatures are presented. The solubilities of crystalline beta-glucose, amorphous beta-glucose, and amorphous beta-glucose in 2-methyl-2-butanol at 60 degreesC have also been measured. The results show that the solubilities of the amorphous forms in 2-methyl-2-butanol are higher than that of the corresponding crystalline form. The presence of dimethyl sulfoxide significantly increases glucose solubility in 2- methyl-2-butanol. Finally, the presence of glucose ester increases glucose solubility in 2-methyl-2-butanol, while the presence of fatty acid has the opposite effect

Controle et conduite automatique de fermenteurs. Mise au point d'estimateurs et de commandes utilisant les modeles physiologiques

CNRS AR 13379 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc

Commande adaptative de procedes de fermentation: mise au point d'estimateurs en ligne et de strategie de controle a l'aide du filtre de Kalman etendu

SIGLECNRS RP 440 (338) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Recherche des relations cisaillement-activite biologique de cellules par l'emploi d'une technique photophysique

SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : RP 440 (353) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc