The Catalytic Performance of Ni-Co/Beta Zeolite Catalysts in Fischer-Tropsch Synthesis

Abstract

The influence of nickel introduction on the catalytic performance of cobalt micro- and mesoporous Beta zeolite catalysts in Fischer–Tropsch Synthesis was studied. Catalysts containing 3 wt% of nickel and 10 wt% of cobalt were prepared by co-impregnation and sequential impregnation and comprehensively characterized by XRD, XPS, NH3-TPD, TPR-H2 and TEM EDX techniques. Neither the dealumination of Beta zeolite nor the incorporation of Co and Ni affected its structure, as shown by XRD and BET investigations. The presence of nickel results in the decrease in the temperature of the cobalt oxide reduction, evidenced by TPR-H2 and the increase of CO conversion. Among all the tested catalysts, the best catalytic properties in FTS showed that based on microporous dealuminated zeolites with a very high CO conversion, near 100%, and selectivity to liquid products of about 75%. In case of dealuminated samples, the presence of Ni decreased the selectivity to liquid products. All catalysts under study showed high resistance to deactivation during the whole time of synthesis (24 h). The very high stability of nickel-cobalt based Beta catalysts was probably due to the hydrogen spillover from metallic nickel particles to cobalt oxides, which decreased re-oxidation of the active phase, sintering and the creation of the carbon on the catalyst surface. Moreover, the presence of Ni on the surface of cobalt-based Beta catalysts could obstruct the formation of graphitic carbon and, in consequence, delay the deactivation of the catalyst.

Morphology Engineering of γ-Alumina Microgranules as Support of Cobalt Catalysts Used for Fischer–Tropsch Synthesis: An Effective Strategy for Improving Catalytic Performance

“…The high acid sites concentration contribute more to undesirable methane selectivity. Moreover, the decrease in catalysts acidity results in the formation of a smaller amount of carbon deposition in surface of catalyst …”

“…Moreover, the decrease in catalysts acidity results in the formation of a smaller amount of carbon deposition in surface of catalyst. 70 To investigate the effect of drying route on the surface property and the catalytic performance, NH 3 -TPD measure- ments were performed to determine the total acidity of the synthesized γ-alumina microgranules. As can be seen in Figure 9, the two-step desorption of ammonia is observed.…”

Hydrogen-Rich Gas Production by Upgrading of Biomass Pyrolysis Vapors over NiBEA Catalyst: Impact of Dealumination and Preparation Method

“…The obtained materials containing 20 wt % of nickel were labeled as Ni 20 HAlBEA (I), Ni 20 HAlBEA (II), Ni 20 SiBEA (I), and Ni 20 SiBEA (II), respectively. The preparation procedure of Ni 20 HAlBEA and Ni 20 SiBEA zeolite catalysts is identical to that described in our previous paper where the scheme of the synthesis of catalysts has been presented …”

“…The preparation procedure of Ni 20 HAlBEA and Ni 20 SiBEA zeolite catalysts is identical to that described in our previous paper where the scheme of the synthesis of catalysts has been presented. 33 Ni 20 HZSM-5 catalyst was obtained by wet impregnation of HZSM-5 (Si/Al = 50) using Ni(NO 3 ) 2 •6H 2 O aqueous solution (pH 2.6−3.0) as a Ni precursor. The obtained suspension was stirred for 24 h at room temperature.…”

Selective Oxidation of Cyclohexene over the Mesoporous H-Beta Zeolite on Copper/Nickel Bimetal Catalyst in Continuous Reactor

“…Beta zeolites have been widely researched as a substrate, and Cu , or Fe-modified samples have demonstrated outstanding activity. , Due to the various functionalities and synergistic effects generated from binary metals, bimetallic cation-exchange zeolite catalysts have recently attracted a great deal of interest. Studies on the dependency of activity, as well as stability in H-Beta zeolite support, are conducted on various bimetallic catalysts consisting of W, Pd, Pt, Rh, Ru, − Cu, Ni, , Sr, Zr, and Zn. − Metal species are well-established to be incorporated into pore-filled substances, such as mesoporous molecules. In comparison to a single metal, the bimetallic alloy exhibits higher activity levels .…”