Effect of sulfur on the catalytic performance of Fe–Ni/Al2O3 catalysts for light olefins production

• Fe–Ni catalysts were studied for light olefins production.
• The catalyst promoted with K2S showed high selectivity to C2–C4 olefins.
• The reaction conditions were found 340 °C, 1 atm, H2/CO = 2/1 and GHSV = 3000 h−1.
• Methane selectivity decreased by using promoted Fe–Ni catalyst.

The effects of sulfur (S) on the catalytic behavior of alumina supported iron–nickel catalysts for the conversion of synthesis gas to the light olefins were studied. Catalytic evaluation results indicated that the CO conversion, CH4 and light olefins selectivity were affected by level of sulfur in the composition of catalyst. The catalytic performance of modified catalysts with sulfur has been investigated in different operational conditions such as H2/CO molar feed ratios, gas hourly space velocity (GHSV), reaction temperature and reaction total pressure. The results showed that the best operational conditions for Fe–Ni/Al2O3 catalyst promoted with 0.15 wt% of K2S are 340 °C, GHSV = 3000 h−1, H2/CO molar ratio 2/1 under atmospheric pressure. The catalysts were characterized by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and N2 physisorption methods.