The effectiveness of the ultrasonication (US) and chelating agents in the dispersion of NiMo supported on activated carbon were examined. Accordingly, NiMo catalysts supported on carbon were prepared through co-impregnation of the support using US or the addition of chelating agents namely citric acid (CA) or ethylenediaminetetraacetic acid (EDTA) to facilitate the dispersion of the metals on the support. A surface area analyzer was used to provide the BET surface area measurements. Fourier-transform infrared spectroscopy (FTIR) and a powder X-ray diffractometer were used for the characterization of the structure of the prepared materials. Scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) analysis of the morphology and surfaces of the mapping of the prepared material was obtained to get insight into the metal dispersion on the support. Results revealed a uniform dispersion of the nickel and molybdenum particles on carbon, especially in the case of using EDTA as a dispersion agent. Hydrodesulphurization of dibenzothiophene on the prepared catalysts was tested in a high-pressure batch reactor 1000 ppm dibenzothiophene in decalin as a model fuel. The results indicated that the chelating agents have a positive impact on hydrodesulphurization (HDS) efficacy and the EDTA has more effect than others. 97 % HDS was achieved using NiMo/AC(EDTA) while 94 % and 92 % were obtained using NiMo/AC(CA) and NiMo/AC(US), compared to 89 % without the use of US and chelating agents.
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