| Summary: | The carburization behaviour of nickel molybdenum trioxide (Ni-MoO3) catalyst with different loading of Ni has been studied by using temperature programmed reduction (TPR) with exposure of 60 vol. % CO in 40 vol. % helium as a reductant. The Ni-MoO3 catalysts were prepared by using the conservative wet impregnation method. The carburization characteristics of prepared catalysts were examined by isothermal carburization mode at 700°C for 90 minutes. The carburized phases were characterized by using X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and field emission scanning electron microscopy (FESEM). XRD pattern for undoped MoO3 show the formation of molybdenum dioxide (MoO2) (2θ=37° and 74.10°) and Mo2C (2θ=33.63° and 62.50°). After addition of nickel at higher loading which is 3% (wt./wt.) of Ni-MoO3 show the XRD pattern obtained Mo2C at at 2θ=61.47°. This is showing that the higher loading of nickel in MoO3 lead to higher reducibility compared 1% (wt./wt.) of Ni-MoO3 but the broad and weak peak resulted from XRD pattern. By calculating the crystallites size 7.11 nm for 3% (wt./wt.) Ni-MoO3 catalyst give the higher crystallinity compared to 1% (wt./wt.) Ni-MoO3 catalyst which is 5.70 nm. Physical analysis by using BET showed an increasing in surface area and pore size of MoO3 catalyst after addition of Ni metal loading. This proves that the higher the addition of loading might attribute to the increasing in active site for enhancing the carburization process which lead to the formation of Mo2C. The slightly phase covering the surface of the particles or seemed like an agglomerate is amorphous deposited carbon that formed between the platelet shape on Ni-MoO3 surfaces were observed through the FESEM images indicating some morphology modification occurred on MoO3. Based on these results, it is interesting to address that the addition of Ni metal to MoO13 has a remarkable influence in carburization process. The 3% (wt./wt.) of Ni on MoO3 catalyst was sufficient to promote the formation of Mo2C. © 2024 Author(s).
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