HYDROLYTIC HYDROGENATION OF INULIN WITH USE MAGNETIC-SEPARATE Ru-CONTAINING CATALYST

The combined hydrolysis and hydrogenation of inulin was studied on Ru-containing magnetically recoverable catalyst, using subcritical water as solvent. The Ru−Fe3O4−SiO2 catalysts are synthesized by incorporation of magnetite nanoparticles (NPs) in mesoporous silica pores followed by formation of 2 nm Ru NPs. The latter was obtained by thermal decomposition of ruthenium acetylacetonate in the pores. Magnetic properties of Fe3O4−SiO2 are typical for superparamagnetic iron oxide NPs of comparable size and allow to make a fast magnetic separation of the catalyst. The results of liquid nitrogen adsorption measurements are typical for mesoporous materials. The BET surface area of catalyst is 280 m2/g, what is allowed for mesoporous catalytic materials. The XPS spectra of Ru-Fe3O4-SiO2 demonstrate a good homogeneity of the sample. The catalyst was tested in hydrolytic hydrogenation of inulin. Inulin is hydrolyzed with formation of fructose and a small amount of glucose. There is a hydrogenation of fructose and glucose in hydrogen with receiving a mannitol and sorbitol, respectively. Mannitol is widely used in production of medicines and pharmaceutics, liquid fuel, the chemical and food industry, biotechnology and production of cosmetics. Mannitol presents in many plants and seaweeds. However, the extraction of mannitol from these raw materials is not a profitable process. Instead, fermentation and catalytic hydrogenation processes are used industrially. Nowadays, mannitol can be obtained by catalytic hydrogenation of monosaccharides like fructose or from glucose-fructose mixtures, using heterogeneous catalyst. During the researches key parameters of process, such as temperature and time of reaction, partial pressure of hydrogen are varied. At optimum reaction conditions: temperature of 150 °C, partial pressure of hydrogen of 60 bars in 45 min, – conversion of inulin was achieved of 100 %, a mannitol yield was 44.3 %. The used catalyst has shown high activity and stability in hydrothermal conditions. Stable magnetic properties of the catalyst cause his easy separation from reactionary mixture by means of external magnetic field.Forcitation:Ratkevich E.A., Manaenkov O.V., Matveeva V.G., Kislitza O.V., Sulman E.M. The hydrolytic hydrogenation of inulin catalyzed by Ru-containing magnetically recoverable catalyst. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 4-5. P. 76-81