A feasibility study of extracting chlorophylls from stinging nettle (Urtica dioica L.) by solvent extraction was performed. Preliminary studies included three different parts of plant material, different preservation techniques and different storage temperatures. Extracts were analysed on content of chlorophyll A and chlorophyll B by HPLC method. Research work showed that stinging nettle could be used as a good natural, low-cost green pigment source, and that ultra-sound assisted extraction is a promising alternative extraction technique resulting in highest efficiency of extraction.
Wax esters have high significance in lubricant, cosmetic and pharmaceutical industries. Research was focused on a thermodynamic interpretation of the lauryl oleate biosynthesis of wax esters in dense carbon dioxide at sub-critical conditions to develop a biocatalytic process gaining deeper insight into the pressure effect on the reaction rate and demonstrating that carbon dioxide displays the following attributes: stability, economy and safety.
Esterification of citronellol with lauric acid, catalyzed by immobilized lipase B from Candida antarctica (Novozym 435), was performed in SC CO2 in the presence of different co-solvents, organic solvents and ionic liquids. Optimal reaction temperature and pressure were determined and the concentration of co-solvent in SC CO2 was optimized. Enzymatic synthesis of in SC CO2/organic solvent and SC CO2/ionic liquids media proved to be an effective preparative method for the synthesis of terpene fatty acid esters applicable in food industry.
Silica monolith aerogels with different degrees of hydrophobicity were prepared. The aerogels, based on TMOS (tetramethoxysilane) precursor, are hydrophilic due to -OH functional groups on aerogel surface, because they promote the adsorption of water. Measurement showed that silica aerogels in comparison to granulated active carbon (GAC) exhibit capacities which are from 15 to 400 times higher for all tested compounds and they remain stable even after 20 adsorption/desorption cycles.
Calculation of flow – pressure conditions in pipe system with two –phase flow The research deals with flow of two – phase mixture. With developed mathematical model and computer program it is possible to determine the type of phase flow, the values of characteristic parameters and pressure drops in pipe sections. These results are vital for optimal design and for processing pipe networks for the transport of two-phase mixtures. Nonlinear mathematical model was solved with the linear theory method (LTM).