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Glycerolysis of rapeseed oil over several solid bases using fixed bed flow reactor has been studied. It was found that Mg-Al hydrotalcite and Al 2 O 3 supported CaO-ZnO demonstrate high activity in this reaction. The yield of monoglycerides reaches 70 % with 96 % oil conversion at 513 K. It was shown that pores size of a catalyst is an important factor of intensification of the glycerolysis process. It was found that turpentine additive decreases the reaction temperature due to higher solubility of glycerol in oil.

The lactide is monomer for production of polylac- tide – biodegradable polymer that use as an ecological packagingmaterial. In an industry the two-stage lactide synthesis is applied. At first, lactic acid condenses into the oligomer using Sn-octanoate catalyst, then oligo- mer depolymerizes to lactide. The drawbacks of this liquid-phase method are a significant amount of by- products — dimers and trimers of lactic acid and low lactide yield.Now a direct vapor-phase condensation of lactic acid and its esters to lactide is considered as alternative to the industrial process. One-stage lactide obtaining and use of solid catalysts are advantages of such method. In this work, the vapor-phase transfor- mation of ethyl lactate over supported TiO2/SiO2 and TiO2/Al2O3 oxides in nitrogen flow at 200–300 °С was studied. The oxide samples were obtained by impregnating silica gel and γ -alumina with an approp- riate amount of titanium tetrabutoxide solution in iso- propanol, then dried at 80 oC, and finally calcined at 500 oC in air for 4 h. The catalysts were characterized by BET method, X-ray diffraction and UV-Vis diffuse reflectance spectroscopy. Catalytic experi- ments were carried out in a steel flow reactor at 200 –270 °С and atmospheric pressure. The load on a ca-talyst was varied in the interval of 8.2–36.4 mmol ethyllactate/(gcat⋅ h) that corresponds gas hourly space velo- city of the mixture of ethyl lactate and nitrogen of 1230–1490 h–1. It was shown that TiO2/SiO2 with5 wt.% content of titanium dioxide provides 48 % conversion of ethyl lactate with selectivity and pro- ductivity towards lactide 74 % and 7.0 mmol/(gcat⋅ h)at 270 °C, respectively. It was found thatTiO2/SiO2 is more efficiently for lactide producing (STY = 6.2 mmol/(gcat⋅ h) compared to TiO2/Al2O3catalyst (STY =1.8 mmol/(gcat⋅ h). It was shown that spent TiO2/ SiO2 catalyst fully restores activity after regenerati- on in air at 500 °С for 2 h. The two-stage scheme of ethyl lactate condensation with the participation of coordina- tion-unsaturated titanium ions is discussed.