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Title:Kromatografija s superkritičnimi fluidi v preparativnem in produkcijskem merilu
Authors:Oman, Miha (Author)
Knez, Željko (Mentor) More about this mentor... New window
Škerget, Mojca (Co-mentor)
Files:.pdf DR_Oman_Miha_2014.pdf (4,65 MB)
 
Language:Slovenian
Work type:Dissertation (m)
Typology:2.08 - Doctoral Dissertation
Organization:FKKT - Faculty of Chemistry and Chemical Engineering
Abstract:V doktorski disertaciji smo se najprej seznanili s superkritičnimi fluidi in visokotlačnimi separacijskimi procesi. Pri pregledu literature smo ugotovili, da se največ raziskav nanaša na izolacijo biološko aktivnih komponent iz rastlinskih materialov s pomočjo superkritične ekstrakcije. S pregledom literature smo ugotovili, da superkritični fluidi omogočajo separacijo številnih komponent iz rastlinskih materialov. Superkritični fluidi so v večini primerov stisljivi mediji, ki so pri sobnih pogojih plini, s čimer dobimo produkte, kjer ni toksičnih organskih topil. Zaradi tega porabimo manj energije in je hkrati manj emisij v ozračje. Oboje pa izrazito pripomore k trajnostnemu razvoju. Superkritična ekstrakcija, kot tudi ostale ekstrakcijske metode, ni povsem selektivna, saj z želenimi biološko aktivnimi komponentami ekstrahiramo še druge komponente. Selektivno ločevanje lahko opravimo s kromatografskimi tehnikami, kot so tekočinska kromatografija, plinska kromatografija in superkritična kromatografija. Slednja je relativno nova metoda, ki se je razvila šele v zadnjem desetletju. V doktorski disertaciji smo raziskali uporabo superkritične kromatografije v analitskem merilu. Na analitski napravi za superkritično kromatografijo smo na testnih komponentah teofilin in kofein, ki sta obe farmakološki učinkovini, preiskovali posamezne vplive procesnih parametrov na separacijo. V nadaljevanju smo dobljene rezultate vključili v raziskavo povečevanja obsega in zagon pilotne preparativne naprave za superkritično kromatografijo, ki je po velikosti med največjimi podobnimi napravami v svetovnem merilu. Na analitski napravi za superkritično kromatografijo smo na koloni s silicijevim dioksidom raziskovali vpliv tlaka, vpliv temperature, vpliv sestave mobilne faze in vpliv posameznih lastnosti stacionarne faze. V superkritični kromatografiji se najpogosteje uporablja CO2 v superkritičnem stanju. Pri separaciji polarnih molekul k nepolarnemu CO2 dodamo so-topilo (modifikacijsko sredstvo mobilne faze). Najpogosteje uporabimo kot so-topilo etanol, metanol, acetonitril, 2-propanol idr. Ugotovili smo, da sta vpliva tipa so-topila in koncentracije so-topila v mobilni fazi med vsemi najbolj izrazita. Kar pomeni, da se kromatografski parametri pri tem najbolj izrazito spremenijo. Vpliva tlaka in temperature na separacijo s superkritično kromatografijo sta manj izrazita, ampak še vedno pomemben faktor, mnogo bolj kakor v tekočinski kromatografiji. Vse ugotovitve posameznih vplivov smo uporabili za zagon pilotne preparativne naprave za superkritično kromatografijo. Pred tem smo spoznali vse sestavne dele in preučili delovanje. Nato smo določili področje delovanja naprave, glede na omejitve naprave in glede na lastnosti superkritičnih fluidov. Pri pogojih, pri katerih smo na pilotni preparativni napravi izvedli separacijo smo opravili številne raziskave. Kljub temu, da smo predhodno dosegli separacijo obeh testnih komponent na analitski napravi za SFC, pa pri podobnih pogojih na pilotni preparativni napravi za superkritično kromatografijo separacije nismo dosegli. Zaradi tega smo izvedli še dodatne eksperimente. S spreminjanjem posameznih procesnih parametrov smo dosegli separacijo z delno prekrivajočimi vrhovi, ki jih je bilo kljub prekrivanju mogoče ločeno zbirati v zbiralne posode naprave. Na podlagi separacije testnih komponent smo pripravili metodo za separiranje biološko aktivnih komponent iz rastlinskih ekstraktov.
Keywords:Superkritična kromatografija, povečevanje obsega, preparativna superkritična kromatografija, produkcijsko merilo.
Year of publishing:2014
Publisher:[M. Oman]
Source:Maribor
UDC:543.5544.16:54-139(043.3)
COBISS_ID:18201878 Link is opened in a new window
NUK URN:URN:SI:UM:DK:P9G2EWIV
Views:1299
Downloads:204
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Categories:KTFMB - FKKT
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Secondary language

Language:English
Title:Supercritical chromatography in preparative and production scale
Abstract:In the thesis supercritical fluids and high pressure separation processes were examined. According to literature review the most researches apply to supercritical fluid extraction and isolation of bioactive compound from plant material. Supercritical fluids are in the most cases compressible media, gasses at ambient temperature, therefore products without residues of toxic organic solvents are obtained. Consumption of energy and environment imprint is significantly lower, which greatly contribute to sustainable development. Supercritical extraction isolates variety of compounds from plant material. In order to separate these compounds from each other various chromatographic techniques, such as liquid chromatography, gas chromatography and supercritical fluid chromatography have been applied in the past. Supercritical fluid chromatography is relatively new technique, which was well developed in last decade. In the thesis, supercritical fluid chromatography has been investigated in analytical scale for two test compounds caffeine and theophylline, in order to determine the influence of the process parameters on the chromatographic parameters. Obtained results were used for scale up onto the preparative and production scale, which apparatus is one of the bigger worldwide. Influences of the pressure, temperature, type and concentration of the modifier, and type of the stationary phases have been studied. In supercritical fluid chromatography CO2 is the most frequently solvent used as the mobile phase. If polar compounds are separated, polar modifier, such as methanol, ethanol acetonitrile, iso-propanol etc., are added to the CO2. Chromatographic parameters are the most significantly influenced, when modifier concentration is increased. Pressure and temperature are less significant factor for separation, however it is more important as in liquid chromatography. Afterwards, experiments on analytical scale were conducted, investigations on operating the pilot apparatus were preformed. Regarding on results of the separation on the analytical scale apparatus and regarding on constrains of the equipment, range of process conditions have been determined for test compounds. Several experiments were conducted on pilot preparative scale apparatus at given process conditions. Even though, separation was achieved on analytical scale, such separation was not possible on pilot preparative scale apparatus at similar process conditions. Additionally, several experiments were conducted on the pilot apparatus. With altering the process conditions successful separation has been achieved. However chromatographic signals, which belong to detected compounds, were overlaying. Even though, fractionation was possible. Regarding on obtained results, this method could be applied for separation of real system, such as plant material extracts.
Keywords:supercritical fluid chromatography, Scale-up, Preparative, Production.


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