Processing of Primary Fischer-Tropsch Products

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

The Fischer–Tropsch heavy fraction is a potential feedstock for transport-fuels production through co-processing with fossil fuel fraction. However, there is still the need of developing new and green catalytic materials able to process this feedstock into valuable outputs. The present work studies the co-hydrocracking of the Fisher–Tropsch heavy fraction (FT-res.) with vacuum gas oil (VGO) at different ratios (FT-res. 9:1 VGO, FT-res. 7:3 VGO, and FT-res. 5:5 VGO) using phonolite-based catalysts (5Ni10W/Ph, 5Ni10Mo/Ph, and 5Co10Mo/Ph), paying attention to the overall conversion, yield, and selectivity of the products and properties. The co-processing experiments were carried out in an autoclave reactor at 450 °C, under 50 bars for 1 and 2 h. The phonolite-based catalysts were active in the hydrocracking of FT-res.:VGO mixtures, presenting different yields to gasoline, diesel, and jet fuel fractions, depending on the time of reaction and type of catalyst. Our results enable us to define the most suitable metal transition composition for the phonolite-based support as a hydrocracking catalyst.

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

This paper focuses on the evaluation of the fuel properties of Fischer-Tropsch diesel blends with conventional diesel. Incorporating this advanced fuel into conventional diesel production will enable the use of waste materials and non-food materials as resources, while contributing to a reduction in dependence on crude oil. To evaluate the suitability of using Fischer-Tropsch diesel, cetane number, cetane index, CFPP, density, flash point, heat of combustion, lubricity, viscosity, distillation curve, and fuel composition ratios using multidimensional GC × GC-TOFMS for different blends were measured. It was found that the fuel properties of the blended fuel are comparable to conventional diesel and even outperform conventional fuel in some parameters. All measurements were performed according to current standards, thus ensuring the repeatability of measurements for other research groups or the private sector.

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

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.

Green Diesel: Biomass Feedstocks, Production Technologies, Catalytic Research, Fuel Properties and Performance in Compression Ignition Internal Combustion Engines

The present investigation provides an overview of the current technology related to the green diesel, from the classification and chemistry of the available biomass feedstocks to the possible production technologies and up to the final fuel properties and their effect in modern compression ignition internal combustion engines. Various biomass feedstocks are reviewed paying attention to their specific impact on the production of green diesel. Then, the most prominent production technologies are presented such as the hydro-processing of triglycerides, the upgrading of sugars and starches into C15–C18 saturated hydrocarbons, the upgrading of bio-oil derived by the pyrolysis of lignocellulosic materials and the “Biomass-to-Liquid” (BTL) technology which combines the production of syngas (H2 and CO) from the gasification of biomass with the production of synthetic green diesel through the Fischer-Tropsch process. For each of these technologies the involved chemistry is discussed and the necessary operation conditions for the maximum production yield and the best possible fuel properties are reviewed. Also, the relevant research for appropriate catalysts and catalyst supports is briefly presented. The fuel properties of green diesel are then discussed in comparison to the European and US Standards, to petroleum diesel and Fatty Acid Methyl Esters (FAME) and, finally their effect on the compression ignition engines are analyzed. The analysis concludes that green diesel is an excellent fuel for combustion engines with remarkable properties and significantly lower emissions.

Design and synthesis of Ga-doped ZSM-22 zeolites as highly selective and stable catalysts forn-dodecane isomerization

Ga-Doped ZSM-22 zeolites were synthesized successfullyviaa hydrothermal method and exhibited better catalytic performance inn-dodecane isomerization.

Recent advances in reactors for low-temperature Fischer-Tropsch synthesis: process intensification perspective

The low-temperature Fischer-Tropsch (LTFT) process aims to produce heavy cuts such as wax and diesel. For many years, there have been studies and improvements on the LTFT process to make the existing reactors more efficient. Recent studies have proposed innovative configurations such as monolithic loop and membrane reactors as well as microchannel reactor, which improved the performance of LTFT synthesis. This persuades us to update the existing knowledge about the available reactors. Some fundamental features of the current reactors, which belong to the classes of conventional reactors (fixed-bed reactors and slurry reactors) and innovative reactors, are discussed to assist the selection of the most efficient reactors specifically for heavy-cuts production. Published experimental and theoretical works with respect to developments in reactor technology and significant advances in catalysis (such as using structured packing, foams, and knitted wire as catalyst supports due to their excellent radial mixing properties) of the FT process are analyzed and discussed. Consequently, it is shown that the LTFT innovative reactors have higher CO conversions and selectivity of desired heavy cuts. Furthermore, the place of innovative reactors among conventional reactors in terms of effective process parameters on the product distribution has been estimated.