Inorganic complex precursor route for preparation of high-temperature Fischer–Tropsch synthesis Ni–Co nanocatalysts

Abstract

The effect of the preparation method on the structural properties and activity of Ni–Co catalysts in the Fischer–Tropsch synthesis has been explored. Impregnation, co-precipitation and a novel method, thermal decompositions of inorganic precursor complex, procedures were applied for the generation of the Ni-promoted alumina- or silica-supported cobalt catalysts. The precursors and the catalysts that were obtained from their calcination were characterized by powder X-ray diffraction, thermal gravimetric analysis, Brunauer–Emmett–Teller specific surface area measurements, scanning electron microscopy and Fourier transform infrared spectroscopy. The catalytic performance in Fischer–Tropsch synthesis was investigated for all calcined catalysts in the temperature interval from 280 to 360 °C. The Ni–Co/Al2O3 catalyst prepared by thermal decomposition of [Ni(H2O)6][Co(dipic)2]·2H2O/Al2O3 as a precursor performed optimally for the conversion of synthesis gas to light olefins. The outcomes revealed that this novel procedure is more advantageous than impregnation and co-precipitation methods for the preparation of effective and durable cobalt catalysts for Fischer–Tropsch synthesis.