Hydrocracking of a Heavy Vacuum Gas Oil with Fischer–Tropsch Wax

Abstract

Catalytic hydrocracking represents an optimal process for both heavy petroleum fractions and Fischer–Tropsch (FT) wax upgrading because it offers high flexibility regarding the feedstock, reaction conditions and products’ quality. The hydrocracking of a heavy vacuum gas oil with FT wax was carried out in a continuous-flow catalytic unit with a fixed-bed reactor and a co-current flow of the feedstock and hydrogen at the reaction temperatures of 390, 400 and 410 °C and a pressure of 8 MPa. The increasing reaction temperature and content of the FT wax in the feedstock caused an increasing yield in the gaseous products and a decreasing yield in the liquid products. The utilisation of the higher reaction temperatures and feedstocks containing the FT wax showed a positive influence on the conversion of the fraction boiling above 400 °C to lighter fractions. Although the naphtha and middle distillate fractions obtained via atmospheric and vacuum distillations of the liquid products of hydrocracking did not comply with the particular quality standards of automotive gasolines and diesel fuels, the obtained products still present valuable materials which could be utilised within an oil refinery and in the petrochemical industry.

Internal Combustion Engines and Carbon-Neutral Fuels: A Perspective on Emission Neutrality in the European Union

“…At this time, there is still neither the technical nor economic possibility to obtain E-fuels suitable for use in Compression Ignition (CI) engines, since currently, only the conventional Fischer-Tropsch (FT) process, which uses a blend of CO with H 2 (syngas), enables the production of hydrocarbon mixtures with suitable Cetane Numbers (CNs) [84], but because these mixtures contain a high proportion of n-alkanes, they require additional hydrocracking and isomerization treatments [85]. Alternatively, on the contrary, FT processes could be carried out with E-fuels obtained from secondary processes, carried out with E-fuels such as DME or methanol.…”

Hydrocracking of Heavy Fischer–Tropsch Wax Distillation Residues and Its Blends with Vacuum Gas Oil Using Phonolite-Based Catalysts

“…The produced diesel fraction from the hydrocracking of the mixture of VGO and FT wax had a cetane number 4-6 times higher than the diesel fraction obtained from the hydrocracking of VGO only. The cetane number of 58 and cloud point of −18 • C were observed in the diesel fraction of the coprocessed mixture at 430 • C. In their recent study, Pleyer et al [24] showed that the yield of gaseous products is increased by an increase in the content of the FT wax in the feedstock (HVGO + FT wax), while the yield of liquid products decreased at the same time.…”

“…The cetane number of 58 and cloud point of −18 °C were observed in the diesel fraction of the co-processed mixture at 430 °C. In their recent study, Pleyer et al [ 24 ] showed that the yield of gaseous products is increased by an increase in the content of the FT wax in the feedstock (HVGO + FT wax), while the yield of liquid products decreased at the same time.…”

Advanced Biofuels Based on Fischer–Tropsch Synthesis for Applications in Diesel Engines

“…Biofuels produced by these raw materials include bioethanol from lignocellulosic biomass, biomethanol, or alternative gasoline as a product of the catalytic conversion of synthesis gas, biobutanol from bioethanol, and diesel fuel produced by hydrogenation or transesterification of non-food or used cooking oils. However, from the point of view of circular economics, the production of synthetic fuels formed after pyrolysis of waste plastics into pyrolysis oil [ 12 , 13 , 14 , 15 , 16 ], or the conversion of synthesis gas to Fischer–Tropsch synthesis products, seems most promising [ 17 ].…”