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2. Process Intensification with Microprocess Engineering.

Author

Verdnik, Aleksandra, Pintarič, Zorka Novak, and Kravanja, Zdravko

Subjects
MICROREACTORS, PROCESS optimization, COST analysis, COMPUTER-aided design, MATHEMATICAL programming
Abstract

Microreactors and other microdevices have proven to be very efficient tools for process intensification in chemical production due to high mass and heat transfer, low temperature gradient, fast and efficient mixing, and short residence times. Microreactor technology is becoming an increasingly important concept, already successfully used at laboratory scale and in some cases even at pilot and production scale. However, there are still some issues that need to be explored for this technology to be used more widely, such as automation and integration, synthesis of the optimal configurations of microprocess units, process optimization, and cost analysis. The aim of this work is considering process intensification based on microprocess engineering, to identify the challenges involved and to provide a basis for the development of a computer-aided framework for design, optimization, and synthesis of integrated microprocess systems. At the Faculty of Chemistry and Chemical Engineering in Maribor, the acquisition of microprocesses equipment is planned as part of the ongoing Upgrading national research infrastructures? RIUM project. The main vision for the future is to combine mathematical optimization and synthesis of microprocessing systems with experimental testing of various configurations of microreactors and other devices. Based on experimental data, a library of process models for microdevices would be created as part of the MIPSYN-Global process synthesizer, a new successor to the earlier MIPSYN synthesizer. The goal is to create synergies between laboratory microdevices and mathematical programming for the efficient design and optimization of various process applications based on microtechnology. [ABSTRACT FROM AUTHOR]

Published
2022
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3. Phase equilibria of the systems resveratrol/carbon dioxide and resveratrol/ethanol/carbon dioxide at elevated pressures

Author

Verdnik, Aleksandra and Knez Hrnčič, Maša

Subjects
udc:54-139:544.344(043.2), ternarni sistem, topnost, binary system, fazna ravnotežja, solubility, superkritični fluidi, phase equilibria, binarni sistem, resveratrol, supercritical fluids, ternary system
Abstract

V diplomski nalogi smo določili fazna ravnotežja za binarni sistem (resveratrol/ogljikov dioksid) pri 40 °C ter 60 °C v območju tlakov med 40 in 500 barov ter za ternarni sistem (resveratrol/etanol/ogljikov dioksid) pri 60 °C in tlaku 300 barov. Za določitev topnosti smo uporabili statično-analitično metodo. Meritve smo izvajali v visokotlačni optični celici in tako spremljali dogajanje v celici tekom celotnega eksperimenta. Koncentracijo resveratrola v vzorcu smo izmerili spektrofotometrično. Najprej smo določili vpliv tlaka in temperature na topnost resveratrola v superkritičnem CO2. Na podlagi teh rezultatov smo določili optimalne pogoje, kjer je bila topnost resveratrola v CO2 najvišja. Pri teh pogojih smo nato izmerili topnosti resveratrola v CO2 ob prisotnosti etanola kot sotopila. Za binarni sistem smo preučili tudi vpliv gostote plina na topnost komponente. Rezultati kažejo, da lahko že z majhno spremembo tlaka in temperature vplivamo na spremembo gostote plina in posledično tudi na topnost resveratrola v sistemu. Ugotovili smo, da topnost resveratrola narašča s tlakom do 300 barov, kjer dosežemo maksimalno topnost pri konstantni temperaturi. Topnosti so podane v masnih deležih kot masa resveratrola na maso plina v binarnem sistemu, oz. v masnih deležih kot masa komponente (resveratrol, plin, topilo) na maso celotnega vzorca pri ternarnem sistemu. Topnosti resveratrola v CO2 so zelo nizke, a se z višanjem tlaka in z dodatkom sotopila višajo. Določili smo tudi tališča resveratrola pri visokih tlakih in ugotovili, da se temperatura tališča spreminja v odvisnosti od tlaka. The phase equilibrium of the binary system resveratrol/carbon dioxide has been determined at the temperatures of 40 °C and 60 °C and in the pressure range from 40 bar to 500 bar. Based on the measurements for binary system, the highest solubility has been attained at the temperature of 60 °C and a pressure of 300 bar. Accordingly, solubility in ternary system (resveratrol/ethanol/carbon dioxide) has been measured at 60 °C and a pressure of 300 bar. Solubility was determined by the means of static-analytic method. The measurements were performed in a high-pressure optical cell, allowing a visual observation of the system behavior during the entire experiment. Resveratrol concentrations in the sample were measured using spectrophotometry. The effect of pressure and temperature on the solubility of resveratrol in the supercritical CO2 has been examined. The results indicate that even a small change in pressure and temperature considerably affect solubility. The results on solubility measurements are presented as mass fractions either as mass of resveratrol to mass of gas for the binary system, or mass of component (resveratrol, gas, and solvent) to mass of the entire sample for the tertiary system. The solubility of resveratrol in CO2 is extremely low however, it increases with increasing pressure andby the addition of a co-solvent. Additionally, the melting points of resveratrol at elevated pressures have been investigated and it was found that the melting point temperature varies depending on the pressure.

Published
2018

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