A COMPARATIVE FMR STUDY OF THE REDUCTION OF Co-CONTAINING CATALYSTS FOR THE FISCHER-TROPSCH PROCESS IN HYDROGEN AND SUPERCRITICAL ISOPROPANOL
N. S. Nesterov1, I. I. Simentsova1, V. F. Yudanov1, O. N. Martyanov1,2
1Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
2Novosibirsk National Research State University, Novosibirsk, Russia
Keywords: сверхкритические флюиды, ФМР, гетерогенные катализаторы процесса ФишераТропша, восстановление, in situ, supercritical fluids, FMR, heterogeneous catalysts for the FischerTropsch process, reduction, in situ
Abstract
An in situ comparative study of the reduction of Co-containing catalysts for the Fischer-Tropsch process in hydrogen and supercritical (SC) isopropanol is performed by ferromagnetic resonance (FMR) spectroscopy. According to the FMR data, the reduction of cobalt-containing oxide particles to metal in hydrogen starts at temperatures of ~360°C, which is substantially lower than a temperature of the formation of metal particles of the active phase according to powder X-ray diffraction and differential thermogravimetry data ( Т ~ 450°C). In SC isopropanol, the reduction to Co metal occurs at lower temperatures ( T ~ 245°C) as compared with the reduction temperature for these catalysts in hydrogen. It is shown that the reduction in SC isopropanol can lead to the formation of superparamagnetic Co nanoparticles with a narrow particle size distribution.
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