Influence of structural-dimensional factor and catalytically active additives of Fe2O3/Cr2O3 in α-Al2O3-based membranes on hydrocarbon dehydrogenation

Abstract

A porous, catalytically active membrane based on α-Al2O3 powder with ultrafine additives of MgO+SiC+SiO2 and catalytically active components of Cr2O3 + Fe2O3 was synthesized in one stage. Double-sided compacting at P = 70–100 MPa and sintering at T = 1300°C were used. The open porosity of the resulting membrane was 38%, and the pore size was from 1 to 3 µm. The influence of structural-dimensional factors, such as material morphology, porosity and pore size, on the catalytic characteristics of the synthesized membranes was studied. The dependences of the structural-dimensional factors from the particle size of the initial powders, their ratio in the mixture, as well as on the method and pressure of compaction were established. The obtained catalytic membrane was used for dehydrogenation of isoamylenes into isoprene. At T = 600°C, the yield of isoprene was up to ~9%, the selectivity ~20%. The conversion of the isoamylene fraction was 46%. During 6 hours of the experiment, the decrease in the catalytic activity of the system was not observed.

Keywords

• ceramics
• porous membrane
• dehydrogenation
• isoamylenes
• isoprene