Carbon nanofibres coated with Ni decorated MoS2 nanosheets as catalyst for vacuum residue hydroprocessing

Abstract

Catalysts based on functionalised carbon nanofibers (FCNF) coated with Ni-decorated MoS 2 nanosheets were obtained by direct decomposition of ammonium thiomolybdate and nickel nitrate impregnated on the FCNF under controlled temperature conditions in inert atmosphere. The catalysts were characterised by X-ray Diffraction (XRD), N 2 adsorption, Raman spectroscopy, temperature programmed reduction of sulfur species (TPR-S), NH 3 temperature programmed desorption (NH 3 -TPD) and transmission electron microscopy (TEM). Decomposition temperature was found to have a paramount importance in the formation of uniform MoS 2 slabs, as revealed by the TEM study: at 600 °C, non-uniform covering of the carbon nanofiber (CNF) was observed Higher asphaltene conversions were obtained for the CNF-supported catalysts prepared at 450 °C, which overperformed the Al 2 O 3 -supported benchmark catalyst. However, the catalytic performance in hydrodesulfurisation and hydrodemetallisation of the CNFbased catalysts was slightly lower than that of the benchmark catalyst.

Bio-oil upgrading in supercritical water using Ni-Co catalysts supported on carbon nanofibres

“…50 nm diameter, and they are characterized by an arrangement of the graphitic planes with an inclination of about 30º with respect to the fibre axis. As-prepared CNFs were subjected to a functionalization treatment with HNO 3 at boiling temperature (CNF f ), which is known to increase the amount of oxygen surface groups without modifying the morphology of the CNF, as previously reported [38]. XRD diffractograms of the CNF f (figures not shown) showed the typical prominent reflexion at ca.…”

“…These include the hydrogenation of light alkenes [23][24][25][26][27], aldehydes [21,[28][29][30][31][32][33], polycyclic aromatic hydrocarbons [34], nitrobenzene [35], and cyclohexene [36]. They have also been used in alkene hydroformylation [37], vacuum residue hydroprocessing [38,39], ammonia and Fisher-Tropsch synthesis [40][41][42], cyclohexanol dehydrogenation [43], NO decomposition [44] and aniline oxidation [45,46]. However, CNFs have not been applied to bio-oil upgrading in supercritical water and more research is needed to develop suitable catalysts for this upgrading technology.…”

Catalytic Hydrocracking of a Bitumen‐Derived Asphaltene over NiMo/γ‐Al2O3 at Various Temperatures

“…According to literature, there is still increasing interest in this research field [13][14][15][16][17]. As is well known, asphaltenes play a key role in forming coke and deactivating the catalyst in bitumen hydroprocessing [18][19][20][21].…”

Relationship between carbon morphology and catalyst deactivation in the catalytic decomposition of biogas using Ni, Co and Fe based catalysts

“…NFC are high valuable materials [33] that depending on their structure and surface properties can be employed in different applications such as catalyst support [34,35], anode in Li-ion batteries [36,37] or additive in polymer composites [38,39]. NFC formation during DRM has been extensively reported [6,22,40,41], although scarce information about the NFC characteristics is available in the literature.…”

“…Depending on the future application of the NFC, metals need to be removed. For that purpose, metal elimination can be performed by reflux in concentrated HNO 3 or HNO 3 :H 2 SO 4 mixtures [35,45].…”