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The activity of haematite, magnetite, pyrite and pyrrhotite containing ore catalysts, modified by treatment in a tensile-energy planetary activator mill and by elemental sulphur additions, has been studied in lignite hydrogenation and coal-derived liquid hydrocracking processes. The application of modified ore catalysts resulted in a significant (by two to four times) increasing of lignite conversion...
Catalytic hydrocracking experiments were performed using primary coal extracts, to establish correlations between coal rank and extract reactivities, in isolation from secondary effects associated with the coal dissolution step. A strong correlation was obtained between liquefaction conversion and carbon content of the original coals: R 2 = 0.96. Strong correlations were also found between...
A coal liquefaction extract was hydrocracked in the presence of several metal carbonyls, organometallic catalyst precursors and a mixture of fullerites. Hydrocracking conversions and product quality achieved when using these materials (a set of metal carbonyls, Mo and Ni octoates and Mo naphthenate) were compared with the performance of a commercial presulfided NiMo/Al 2 O 3 supported...
A liquefaction extract of Point of Ayr coal (UK) was hydrocracked using a mixture of fullerenes as dispersed catalyst and tetralin as solvent. Structural characteristics of the hydrocracking products were examined as a function of increasing reaction time and compared with those of products prepared in the absence of catalyst. Comparison of t.g.a.-derived boiling point distributions showed that the...
Twenty-five catalysts of metal oxides principally containing iron were prepared and examined in hydrocracking of coal model compounds: diphenyl ether, diphenylmethane and benzyl phenyl ether. Highly active catalysts were Fe 2 O 3 -I and -II and Fe 2 O 3 -TiO 2 for diphenyl ether, Fe 2 O 3 -I and -II and Fe 2 O 3 -SiO 2 ...
Athabasca bitumen was hydrocracked in a continuous-flow mixed reactor over an Ni-Mo/γ-alumina catalyst at 430°C and 13.7 MPa. Data for the yields of distillate products from single-pass and multi-pass operation of the reactor were fitted to a lumped kinetic model. Cracking reactions were represented as a minimal number of independent reactions by introducing the concept of stoichiometric coefficients...
Hydrotreating Israeli shale oil at 150 atm, an LHSV of 0.5-1.5 h -1 , a temperature of 340-400°C, and a hydrogen to oil ratio of 1500 NL L -1 was studied in a trickle-bed reactor pilot plant packed with two novel catalysts in series. The first catalyst was Ni-Mo supported on wide-pore alumina and the second catalyst was Co-Mo-Cr supported on combined zeolite HY-alumina carrier...
Changes in sample reactivity and catalyst deactivation during the early stages of the hydrocracking of coal liquefaction extracts, using presulphided supported NiMo/Al 2 O 3 and a dispersed Mo catalyst, have been investigated. The characterisation of the liquefaction extract and the hydrocracking products has been made using size exclusion chromatography (SEC), UV-fluorescence spectroscopy...
Hydrocracking of hydrotreated Israeli shale oil and its atmospheric residue was studied at 50atm hydrogen pressure, LHSV 0.5-4.4h -1 , temperature 350 o C and V H2 1500Nl/l in a fixed bed reactor pilot plant with two Ni-Mo-zeolite catalysts based on mono-(HY+Al 2 O 3 ) and bizeolite (HY+H-ZSM-5+Al 2 O 3 ) supports. Desulfurization and...
Different regeneration strategies for a Pt-SO 42- -ZrO 2 catalyst were investigated. Two of the regeneration methods tested on the same deactivated catalyst included sulfur addition via a SO 2 step followed by a reactivation in situ step. These methods produced regenerated catalysts, which were active for the conversion of n-hexadecane. However, their high activity...
Carbonaceous deposits on finely dispersed MoS 2 particulates and a NiMo-supported catalyst, recovered from coal extract hydrocracking experiments, have been examined. Large surges in carbon deposition on catalyst surfaces were observed when using fresh catalyst and fresh feed. When using fresh feed with re-used catalyst, additional but smaller surges in deposition were found. The compositions...
Liquefaction experiments were carried out in spinning/falling basket autoclaves using samples of Kellingly (UK) and Samca (Spain) coals, and a process derived recycle solvent (PDRS). Hydrocracking experiments were carried out in a bomb type autoclave using sulphided NiMo catalyst. For the dissolution experiments with the individual coals, the influence of temperature 380, 400 and 420 o C,...
Tyre crumb samples from two sources, one UK and one Spanish, were liquefied using a process derived recycle solvent (PDRS) or tyre pyrolysis oil (TPO) or a mixture of the two solvents. For PDRS, experiments were carried out at different temperatures (360, 380, 400 o C) and for different times (400 o C, 1 or 2h). For TPO and mixed solvent systems experiments were carried out for 1h...
A sample of Point of Ayr coal extract has been hydrocracked in a microbomb reactor with NiMo on alumina catalyst in tetralin as solvent and hydrogen donor and under hydrogen pressure. The product was separated from solvent and catalyst and then split into equal parts and stored either under nitrogen atmosphere in a freezer or in air at room temperature. Samples of the products were examined at 2h...
The use of supercritical pentane, under increasingly severe conditions of temperature and pressure, allows residual oils to be separated into fractions with progressively higher molecular weight without significant chemical degradation. Characterisation of these individual fractions provides a more complete picture of bitumen resid chemistry than average values determined for the whole sample. In...
Supercritical fluid extraction, narrow-cut characterization of bitumen pitch, hydrocracker and once-through coker vacuum resids revealed the unexpected process chemistry of bitumen hydrocracking. Hydrocracking appears to prolong the coke formation process of the end-cut material of bitumen, by converting it to coke precursors. The conversion (or removal) mechanism for most key species (microcarbon...
The effect of elemental sulfur on the conversion of residue for catalytic hydrocracking of Arabian heavy vacuum residue was tested using an autoclave reactor. The reaction condition was 703K and 5.0MPa of hydrogen partial pressure. Adding only a small amount of sulfur increased the conversion of residue from 64 to 80wt%, as well as the yield of middle distillate from 23 to 31wt%. This should be attributed...
Differences between the behaviour of coal macerals during liquefaction and catalytic hydrocracking were investigated. The liquefaction experiments were carried out in tetralin, using a flowing solvent reactor. The extracts were catalytically hydrocracked in a micro-bomb reactor, using a commercial catalyst. Extracts and hydrocracked products were characterised by size exclusion chromatography (SEC),...
A set of pillared clay catalysts based on montmorillonite (a natural clay) and laponite (a synthetic clay) have been prepared. The new catalysts have been pillared with tin, chromium and aluminium pillars as well as layered double hydroxides based on polyoxo-vanadate and -molybdate. The activities of these novel catalysts have been compared with that of a commercial supported NiMo/Al 2 O ...
Novel catalysts have been prepared, based on montmorillonite (a natural clay) and laponite (a synthetic clay) pillared with tin, chromium and aluminium pillars as well as layered double hydroxides based on polyoxo-vanadate and -molybdate as previously described. These novel catalysts were compared initially with a standard Ni/Mo catalyst supported on alumina and a dispersed catalyst, Mo(CO) 6...
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