Graphene based catalysts for deep hydrodesulfurization of naphtha and diesel fuels: A physiochemical study

In this study, graphene materials have been synthesized with solid camphor (C10H16O) and methane gas as carbon precursors using atmospheric pressure chemical vapor deposition (CVD) technique at a temperature range of 900-1000 degrees C for a period of 45 min over copper nanoparticles. Influence of the carbon precursors upon the shape, number of layers and yield of the synthesized graphene samples has been investigated. In this venue, the compounds synthesized were functionalized with oxygen groups and impregnated by cobalt and molybdenum active phases. Moreover, the total metal loading and Co/Mo weight ratio of prepared compounds were adjusted to their industrial nominal values of 10% and 0.33, respectively. The synthesized compounds were characterized through the Transmission Electron Microscopy (TEM), Raman Spectroscopy and X-ray Diffraction (XRD) techniques as well as; BET-BJH, Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared (FTIR) spectroscopy, Inductively Coupled Plasma (ICP), Temperature Programmed Reduction (TPR), and Temperature Programmed Desorption of ammonia (NH3-TPD) analyses. In terms of synthesis of graphene material, results revealed that graphene sheets with a high yield of 90% and less than 5 layers were obtained from camphor. Ultimately, the evaluations of the HDS of naphtha with 1350 ppm of sulfur demonstrated a considerably higher activity of the carbonaceous based catalysts synthesized (98.5-100% S-removal) compared with the industrialalumina based catalyst (92.6% S-removal). Moreover, as a significant result, the sulfur content of the diesel feed was reduced from 13,000 to 15 ppm using camphoric based catalysts at approximately mild reaction conditions (300 degrees C, 15 bar hydrogen pressure, 100 NL/L H-2/feed ratios, and LHSV of 5 h(-1)). (C) 2015 Published by Elsevier Ltd.