змішування

Змішування в пасивних мікроміксерах залежить від їх геометрії. Отже, багато пасивних мікроміксерів ефективні тільки при великих числах Рейнольдса і вимагають складної структури каналів. Наведено можливості вдосконалення структури Т- мікроміксера для змішування двох рідин з введенням бар’єрів у мікроканалі. У дослідженні ми змінюємо 3 параметри: висоту бар’єра, зсув бар’єра від центру каналу та форму бар’єра. Модель демонструє високу ефективність змішування навіть при малих числах Рейнольдса Re = 0,1.

The dissolution process of potassium chloride particles in the apparatus with two-blade mechanical stirrer was investigated and the mass transfer coefficient was determined. The experimental results were generalized by criterion dependence. The independence of the mass transfer coefficient from the solid particles diameter was confirmed. A countercurrent process of potassium salt dissolution in two apparatuses with a mechanical stirring was considered. A mathematical model for countercurrent dissolution was developed and the efficiency of this process was determined.

The purpose of this work is to investigate the thermodynamic properties of the solubility of methyl 6-methyl-2-oxo-4-phenyl-1,2,3,4-tetrahydro-pyrimidine-5-carboxylate, which exhibits a wide spectrum of biological activity in organic solvents of different polarity and their character of mixing. As you know, the processes of synthesis and purification of solid substances, allmost, occur with the help of individual solvents or their mixture, so optimization of these processes is impossible without determining the thermodynamic parameters of their dissolution.

The temperature dependences of the solubility of 2-methyl-5-(2-chloro-5-trifluoromethylphenyl)-furan-3-carboxylic acid and 2-methyl-5-(2,5-dichlorophenyl)-furan-3-carboxylic acid in acetonitrile, dimethyl ketone, isopropanol and ethyl acetate have been experimentally determined. The enthalpies of fusion of the investigated substances, as well as their enthalpies and entropies of mixing at 298 K have been calculated. The dependence of the saturated solution concentration on the values of enthalpy and entropy of solubility at 298 K has been determined.