Profound synergetic effect of metal oxide promoters and TiO2–SiO2 binary support in cobalt Fischer‐Tropsch catalyst

Abstract

AbstractA series of cobalt catalysts supported on TiO2, SiO2, or a mixture of them, incorporated with some added oxides from Groups III, IV, and V of transition metals, were prepared using the incipient wetness impregnation method. For better evaluation of catalysts, the physicochemical properties of catalysts were investigated using brunauer‐emmett‐teller (BET), H2‐TPR, NH3‐TPD, X‐ray diffraction, X‐ray photoelectron spectroscopy, and transmission electron microscopy techniques. The performance of catalysts was studied in a fixed‐bed reactor at 220°C, 24 bar, gas hourly space velocity (GHSV) of 2 L/h/gcat., and H2 to CO ratio of 2. The results indicate that CeO2 and ZrO2 as promoters can enhance the CO conversion and catalyst activity and enhance the selectivities of higher‐molecular‐weight products. On the contrary, the presence of V2O5 as a promoter undesirably suppressed CO conversion and, consequently, catalytic performance. The results show that the catalyst included CeO2, was supported on a binary mixture of SiO2 and TiO2, and has significant improved activity and C5+ selectivity. From the reactor test, values of 156.48 mmol COconv./gCo/h activity, and 0.17 gC3+/(h.gcat.) productivity have been obtained for this catalyst.