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An approach to model the hydrodesulfurization (HDS) and hydrodemetallization (HDNi and HDV) of a heavy crude oil (21°API and 3.51wt% sulfur) was developed. By using data obtained from an experimental bench-scale reactor at different reaction conditions of LHSV (0.33–1.5h −1 ), temperature (380–420°C) and pressure (6.9MPa) keeping constant the hydrogen-to-oil ratio at 5000stdft 3 /bbl...
One dimensional homogeneous and heterogeneous reactor models and nth-order and two-parallel reactions following first order kinetics were explored in order to compare their capabilities to predict the sulfur content in the liquid product coming from a trickle-bed bench-scale reactor, where hydrodesulfurization of vacuum gas oil took place. Experimental data of sulfur concentration obtained at T=340–380°C,...
Titanyl sulfate (TiOSO 4 ) extracted with sulfuric acid from the mineral ilmenite (FeTiO 3 ), which has a high content of titanium (32.2wt.%) was study as acid solid catalyst for the oleic acid esterification. The maximum extraction of Ti was 98wt.%. As reference catalysts sulfated titania (SO42-–TiO2) and titania (TiO 2 ) were synthesized by sol–gel route using as starting...
The ZoneFlow reactor (Tribute Creations, LLC) is a tubular reactor with two types of internals: a core type and adjacent to the wall, a casing type, both covered with a thin layer of catalyst. It aims for higher energy efficiency and lower steam-to-carbon ratios in methane steam reforming by a judicious design of the relative position of the internals and their geometrical characteristics and a higher...
Different feedstocks (7–21°API gravity, 300–450ppm Ni+V) were hydrotreated in a bench-scale reactor at moderate reaction conditions (70kg/cm 2 , 5000ft 3 /bbl H 2 /oil ratio, 0.5h −1 LHSV) to study the deactivation of a NiMo/γ–Al 2 O 3 commercial catalyst. The experiments were carried out at three temperatures (380, 400 and 420°C) and samples were taken...
Four AlTiMg mixed oxide supports were synthesized by the sol–gel method, adding different MgO loadings (0, 5, 10 and 20wt.%). The samples were characterized by XRD, N 2 physisorption, FT-IR spectroscopy, FT-IR pyridine adsorption and UV–Vis DRS. The supports exhibited amorphous mesoporous structures, with average pore size between 3.8 and 7.8nm and high specific surface areas (170–280m ...
Four different CoMo catalysts supported by alumina, alumina–titania, alumina–silica and carbon were used to study the early stage of deactivation. Hydrodemetallization (HDM) and hydrodesulfurization (HDS) activities of these catalysts have been tested in high pressure, high temperature micro-plant by using heavy crude oil as feed. Thiophene activity of the spent catalysts was compared with the fresh...
The present work is focused on attempt to understand the importance of aromaticity in the elimination of N, O and S atoms from five-membered heterocycles and catalyst poisoning by basic nitrogen six-membered heterocyclic compounds in the hydrotreatment (HDT) process. Pyrrole, furan, thiophene and pyridine, and their fused benzene ring derivatives have been studied by means of density functional theory...
Solid acid catalysts of 12-molybdophosphoric acid (MoP) supported on hydrous zirconia were synthesized using the impregnation method. The solids were characterized by: N 2 adsorption to determine specific surface area and pore size distribution, Thermo-Programmed Desorption (TPD) of NH 3 and CO 2 were employed for the study of acid and base properties, Raman spectroscopy was...
A five-lump model previously reported in the literature was used for the kinetic modeling of an atmospheric residue (312°C+) hydrocracking. The model has ten reaction rate coefficients, makes a distinction of different hydrocarbon groups based on boiling ranges, and includes the following lumps: unconverted vacuum residue (538°C+), vacuum gas oil (VGO; 343–538°C), middle distillates (204–343°C), naphtha...
A study of the influence of reaction parameters (reaction temperature, pressure and catalytic precursor) on the upgrading of Maya heavy oil under low pressure and moderate temperature under slurry conditions is presented. The behavior of the purely thermal hydrotreating system was first characterized to have a basis for distinguishing the effect of incorporating a catalyst in further hydrotreatings...
TiO 2 –ZnO mixed oxides (1.0, 3.0, 5.0 and 10.0wt.% Zn) photoconductors were prepared by the sol–gel method and used for the H 2 production from water splitting. The solids were characterized by nitrogen physisorption, XRD, RAMAN, EDS, UV–Vis and XPS spectroscopy. High specific surface areas (85–159m 2 /g) were obtained in all the mixed oxides compared to the bare TiO 2...
A new mechanistic model for molybdenum sulfide catalysts with cobalt and nickel promoters under hydrodesulfurization reaction conditions is proposed, which includes dynamic migration of sulfur and promoter atoms between adjacent sulfide layers. These migrations are caused by heterolytic dissociation of gas-phase hydrogen and formation of hydride hydrogen on a promoter atom. Hydride hydrogen adsorbed...
Pure and mixed oxides (Al 2 O 3 , ZrO 2 , Al 2 O 3 –MgO, Al 2 O 3 –SiO 2 , Al 2 O 3 –TiO 2 , and Al 2 O 3 –ZrO 2 ) were prepared by homogeneous delayed precipitation. The synthesized supports were impregnated by incipient wetness method to obtain CoMo catalysts. Both supports and catalysts...
In this work we have studied the absorption of H 2 S and CO 2 in NaOH solutions (0.01, 0.1, 0.5, 1 and 2M), in order to treat these acid gases coming from sour gas sweetening process. Our results show that gas dissolution/neutralization is faster at the lowest NaOH concentrations tested in consequence a compromise must be reached between bisulfide–sulfide yield and reaction fastness.
The performance of four coal liquefaction residues (CLRs) in modification of petroleum paving asphalts were investigated. The 40–55 penetration grade modified asphalts were made. ASTM D5710-95 specifications were used to evaluate the modified asphalts. The influence of chemical composition and preparation methods were studied. The results indicate that the performance of CLR mainly depends on the...
Key refinery technologies for upgrading of heavy oils feasible to be combined to increase yield and quality of upgraded oil are reviewed and analyzed. Hydrogen addition and carbon rejection based technologies are described to establish their current situation for heavy oil and residue upgrading. Various integrations of upgrading processes were identified in the literature and others have been proposed,...
Acids solids sulfonated carbons Starbons-300 were prepared by using a mixture of ClSO 3 H/H 2 SO 4 and H 2 SO 4 (98%) as sulfonating agents. Depending on the sulfonation method used important effects were found on the acidity, textural properties and activity. SO 3 H groups linked to the Starbons-300 surface were observed by FTIR photoacustic spectroscopy...
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