Ruthenium promoted cobalt–alumina catalysts for the synthesis of high-molecular-weight solid hydrocarbons from CO and hydrogen

Abstract

The effect of the ruthenium promotion of Fischer–Tropsch (FT) cobalt–alumina catalysts on the temperature of catalyst activation reduction and catalytic properties in the FT process is studied. The addition of 0.2–1 wt % of ruthenium reduces the temperature of reduction activation from 500 to 330–350°C while preserving the catalytic activity and selectivity toward C₅₊ products in FT synthesis. FT ruthenium-promoted Co–Al catalysts are more selective toward higher hydrocarbons; the experimental value of parameter α_ASF of the distribution of paraffinic products for ruthenium-promoted catalysts is 0.93–0.94, allowing us to estimate the selectivity toward C₂₀₊ synthetic waxes to be 48 wt %, and the selectivity toward C₃₅₊ waxes to be 23 wt %. Ruthenium-promoted catalysts also exhibit high selectivity toward olefins.