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Two catalytic systems (CH3OK/CH3OH and CH3OK/tert-BuOH) were tested to estimate competitive interesterification-transesterification processes of rapeseed oil with methyl acetate. Catalyst completely dissolves in methanol, while in tert-butanol suspension was obtained. With CH3OK/CH3OH catalytic system high FAME content was obtained (86 wt%), but triacetin content was negligible and without FAME mostly transesterification products of oil and triacetin were observed (up to 94 wt% of all products). When CH3OK/tert-BuOH catalytic system was used, only interesterification of oil proceeded, nevertheless the composition of product complicated the interesterification of triacetin with tert-butanol.

Composites of Au supported on the TiO2-nanofibers (Au/NF-TiO2) were synthesized and tested in glycerol oxidation processes. TiO2-nanofibers were prepared by a microwave-assisted hydrothermal synthesis method. Chemical deposition method was used for nanofibers modification with Au nanoparticles. Oxidation of aqueous glycerol solutions by molecular oxygen in the presence of Au/NF-TiO2 nanocomposites was performed. It was found that Au/NF-TiO2 composites are catalytically active in alkaline glycerol water solutions. The main product of glycerol catalytic oxidation was glyceric acid, by-products were – tartronic, lactic, glycolic, oxalic, acetic and formic acid. It was shown that Au/NF-TiO2 catalysts’ activity and selectivity depend on Au weight loading, glycerol/Au molar ratio, oxygen pressure and NaOH initial concentration. The best result was achieved using the 0.5 wt%Au/NF-TiO2 catalyst: selectivity by glyceric acid was 76% with glycerol conversion 100%.

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