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Interesterification of vegetable oils is one of the methods which have been considered for biodiesel production. Average yield of fatty acid methyl esters (FAME)/triacetin (TA) containing product mixture obtained under developed optimal rapeseed oil (RO) interesterification reaction conditions reached 117.2%. Treatment of FAME/TA mixture with three different commercial ion exchange resins (Amberlyst-A26 (OH-), Amberlyst-15 (H+), Lewatit GF 202 (Na+)) and water was investigated to improve fuel properties or extract FAME and TA as two separate marketable products. Fuel properties of obtained product mixtures were relatively close to biodiesel obtained from RO by transesterification reaction with methanol. The highest influence on chemical composition of product mixture showed water as treatment agent. Water can be successfully used as extraction agent for separation of TA and other glycerol (G) acetates from fatty acid moiety containing compounds. Two separate product mixtures were obtained after treatment of FAME/TA containing mixture with water. G (~5 wt.%), DAG (~33 wt%) and TA (~61 wt.%) mixture extracted with water using developed method has high potential for application in different industrial areas. Rest of product mixture with high content of FAME (~77 wt.%) could be used as renewable fuel for diesel engine exploitation.

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.

A convenient method for the analysis of commercial acetylated glycerol samples based on 13 C NMR is presented with the accuracy comparable to the standard gas chromatography approaches. The advantage of method is that it does not need any sample derivatization procedure by silyl groups and its appli cation is much more straightforward, as compared to the published 1 H NMR method.