A continuously operated ?-shaped microreactor was used for lipase-catalyzed synthesis of isoamyl acetate in the 1-butyl-3-methylpyridinium dicyanamide/n-heptane two-phase system. At preliminarily selected conditions the amount of produced isoamyl acetate was almost three-fold better as compared to the intensely mixed batch process. This was mainly a consequence of efficient reaction–diffusion dynamics in the microchannel system, where the developed flow pattern comprising of intense emulsification provided a large interfacial area for the reaction and simultaneous product extraction.
COBISS.SI-ID: 30820357
Laccase-catalyzed L-DOPA oxidation in an oxygen-saturated water solution was studied in a y-shaped microreactor. In a given microreactor geometry, up to 87% conversions of L-DOPA were achieved at residence times below 2 min. A two-dimensional mathematical model composed of convection, diffusion, and enzyme reaction terms was developed. Model simulations, obtained by a non-equidistant finite differences numerical solution of a complex equation system, were proved and verified in a set of experiments performed in a microreactor.
COBISS.SI-ID: 30163717
A lipase-catalyzed synthesis of isoamyl acetate was studied in a continuous microreactor. The esterification occurred at n-hexane and aqueous phase with dissolved lipase B interface. By establishing parallel laminar flow with liquid–liquid boundary in the microchannel, a separation of phases was achieved at the y-shaped exit of the microreactor, which enabled continuous separation of product. A 3D mathematical model was developed, considering the velocity profile, convection, diffusion, and enzyme reaction terms. Results demonstrated higher conversions than in any literature reported so far.
COBISS.SI-ID: 30545413
Paper focuses on structural, thermal and mechanical properties of nanocomposites in dependence of preparation method and poly(methyl mathacrylate) /organically modified montmorillonite ratio. Nanocomposites were prepared by bulk polymerization and by melt compounding. It was observed that nanocomposites prepared via melt compounding had a highly oriented structure with lower interlayer spacing values than nanocomposites prepared via bulk polymerization. Two reasons for the observed smaller interlayer spacing obtained by melt compounding were identified and discussed in detail.
COBISS.SI-ID: 29809925
The chemistry of peroxide crosslinking was considered with the intention of the development of a fundamental kinetic model for the crosslinking process. The kinetics of the crosslinking of several elastomers by different organic peroxides was studied. The proposed reaction mechanisms were critically evaluated with the objective of developing a general description of the governing chemistry. A novel fundamental kinetic model was developed. Its simulation was able to describe the complete crosslinking process for a wide range of compositions and assortment of elastomers.
COBISS.SI-ID: 30003205