КАТАЛИТИЧЕСКИЙ ГИДРОГЕНОЛИЗ ДИМЕТИЛФЕНИЛКАРБИНОЛА

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A comparative study of the activity of heterogeneous catalysts in the heterophase reaction of dimethylphenylcarbinol hydrogenolysis was carried out: commercial copper-chromobarium (CChB); hydrothermally modified commercial aluminum oxide (HTT-OA); copper catalyst based on HTT-OA (Cu+ZnO)/HTT-OA); copper catalyst based on Fe-pillar aluminosilicate (Cu/Fe-PilAlSi); tungsten oxide deposited on aluminum oxide (WO3/OA). The porous structure of the catalysts was characterized by low-temperature nitrogen adsorption-desorption method, and the disperse composition was characterized by laser diffraction. The microporous component in the pore structure of the catalysts is absent or weakly expressed, and the mesoporous component is formed by slit-like pores. The pore volume of Cu/Fe-PilAlSi is mainly formed by pores smaller than 5 nm, the other samples - by pores larger than 5 nm. All investigated objects are polydisperse systems with particle size variation in the ranges: Cu/Fe-PilAlSi 0,1-100 μm, CChB 1-100 μm, the rest 2-1000 μm with the fraction of particles up to 100 μm within ~ 50 ±10%. The choice of the temperature of catalytic experiments ~ 160°C as the maximum temperature at which the rate of thermal dehydration can be neglected was justified. It was found that all copper-containing catalysts exhibit bifunctional properties: dehydration activity increases in the series (Cu+ZnO)/HTT-OA << CChB < Cu/Fe-PilAlSi, hydrogenating activity - in the series Cu/Fe-PilAlSi << (Cu+ZnO)/HTT-OA < CChB. The Cu/Fe-PilAlSi catalyst along with the dehydrating ability shows activity in the oligomerization reaction of α-methylstyrene. In the case of using the binary catalyst system "(Cu+ZnO)/HTT-OA + WO3/OA" for the hydrogenolysis of dimethylphenylcarbinol, the mass loading of the catalyst with the hydrating function should exceed the loading of the catalyst with the dehydrating function by at least two times.