Hydrocracking Of Residue Research Articles

Adsorptive Desulfurization of the Gasoline Obtained from Low-Pressure Hydrocracking of the Vacuum Residue Using a Nickel/Bentonite Catalyst

In this paper, adsorptive desulfurization of the gasoline produced from low-pressure hydrocracking of the atmospheric residue was studied. Gasoline obtained from such a process has a high sulfur content and is not suitable for use as a motor fuel without further desulfurization. A nickel-modified natural bentonite catalyst was developed and used in the process. The reaction temperature and flow rate were adjusted to maximize the sulfur removal efficiency while fixing the pressure at 2.5 MPa. Optimal sulfur removal was obtained at 270 °C and 1.0 h–1 feed rate, reducing the gasoline sulfur level from 450 to 32 ppm without affecting the hydrocarbon content and, hence, preserving the octane number. Sulfur adsorbs on nickel nanoparticles by forming nickel sulfide, and the catalyst can be regenerated by subsequent oxidation with air, followed by reduction with hydrogen gas.

Novel Ebullated Bed Residue Hydrocracking Process

Residue hydrocracking has been attracting more and more attention to the refining industry in recent years, and one of the best approaches is ebullated bed residue hydrocracking (EBRH). STRONG ebullated bed residue hydrocracking uses a new type of reactor, and a 50 KTA demonstration unit has been put into operation now. Crucial points of STRONG residue hydrocracking are proposed physical and chemical properties of a solid catalyst, flow mechanism, efficient separation of gas–liquid–solid in the reactor, and reaction performance within various scales of the pilot tests. The results showed that the STRONG reactor with a microspherical catalyst inside a canceled recycling pump inside and outside overcame mass transfer difficulties, solved diffusion control problems, and created high catalyst efficiency to reduce catalyst consumption. To prevent the catalyst from being entrained from the reactor, a triphase separator was used and the amount of catalyst carried off was less than 1 μg/g.

Effect of Metal Loading in NiMo/Al2O3 Catalysts on Maya Vacuum Residue Hydrocracking

Hydrocracking catalysts with large porosity need to be developed to treat heavy oil feedstocks rich in large molecular weight components such as asphaltenes and withstand deactivation due to coke formation. In this work, catalysts were prepared by impregnation of varying NiMo loadings on a mesoporous Al2O3 support. The effect of metal loading on the hydrocracking of a vacuum residue at three temperatures (400, 425, and 450 °C) was studied in a batch microbomb reactor. Catalysts were reutilized in a second reaction with fresh feed to assess their activity following the initial period where results are dominated by a large carbon deposition. The textural properties and the coke content on the spent catalysts were evaluated after both reactions. It was found that the reaction temperature had an important effect on the conversion of the fraction with a boiling point above 450 °C, whereas metal loading had minimal impact. On the other hand, metal loading had a significant effect on hydrodeasphaltenization (HDA...

Slurry-Phase Hydrocracking of Residue with Ultradispersed MoS2 Catalysts Prepared by Microemulsion Methods

Slurry-phase hydrocracking of vacuum residue using a dispersed catalyst has been investigated in this work. The liquid yield and coke formation in this process mostly depend upon the catalyst particle size and its distribution. Three emulsion methods, colloidal emulsion liquid (CEL), emulsion liquid membrane (ELM), and reverse micelle (RM), are used to synthesize the dispersed MoS2 catalyst. Dynamic light scattering results show that the colloidal particle of molybdenum sulfide in the RM catalyst is smaller in size and narrowly distributed in comparison to the catalysts prepared by CEL and ELM methods. Our scanning electron microscopy and transmission electron microscopy analysis results also support the smaller particle size of the active metal in the RM catalyst. Hydrotreating and hydrocracking activities of the RM catalyst are higher, and it is due to its smaller particle size and its narrow distribution. Moreover, coke formation in this catalyst is very low. It is found that the residue (550 °C+ hydro...

Thermal Cracking and Catalytic Hydrocracking of a Colombian Vacuum Residue and Its Maltenes and Asphaltenes Fractions in Toluene

Thermal cracking and catalytic (molybdenum naphthenate) hydrocracking processes in toluene solvent were carried out in a batch reactor for a typical Colombian heavy vacuum residue and its corresponding separated maltenes and asphaltenes fractions. The thermal cracking and catalytic hydrocracking tests were performed at 430 °C and 13.5 MPa for 25 min in the presence of nitrogen and hydrogen, respectively. Additionally, catalytic hydrocracking was also conducted after conditioning the vacuum residue at 380 °C, and 12.2 MPa of H2 for 60 min with activated carbon. The cracking and catalytic hydrocracking performances of the vacuum residue and its components (maltenes and asphaltenes) were assessed by evaluating the effects on the yield and quality of the products (gas, toluene-insoluble solid, and liquid) utilizing SARA (saturates, aromatics, resins, and asphaltenes) composition and removal of sulfur and heavy (Ni, V) metals analyses. The vacuum residue showed asphaltene conversions of 53.1 and 43.1 wt % (exc...

Effects of Surface Modification on the Catalytic Performances of Nickel Sulfide Nanocatalysts for Residue Hydrocracking: A Monte Carlo Simulation and Experimental Study

AbstractSaturates, aromatics, resin, and C7 asphaltene (SARA) fractions of feedstock were analyzed systematically, and molecular models were constructed. The Monte Carlo method was utilized to investigate the intermolecular interactions between SARA fractions and the ligands absorbed on nickel sulfide nanocatalysts. Additionally, the structural characteristics of the hydrocracked products were analyzed by using elemental analysis, 1H NMR spectroscopy, and FTIR spectroscopy to study the effect of surface modification on the catalytic performances of nickel sulfide nanocatalysts. Simulation results reveal that oleic acid and 1‐dodecanethiol have a better miscibility with aromatic fractions of residue than cetyltrimethyl ammonium bromide and that oleic acid has a high affinity and selectivity to C7 asphaltene. Adsorption experiments show that nickel sulfide nanocatalysts modified with oleic acid and 1‐dodecanethiol present a certain “core affinity” in the diffusion of residue colloid, which leads to a higher catalyst concentration in C7 asphaltene than the average value in the feedstock. Subsequently, experimental data demonstrate that surface modification with oleic acid and 1‐dodecanethiol enhances the catalytic activity of nickel sulfide nanocatalysts, which also facilitates the hydrogenation of C7 asphaltene. Furthermore, nickel sulfide nanocatalysts modified with oleic acid show the best hydrogenation and anticoke activity because of the affinity between oleic acid and C7 asphaltene.

Effects of dispersed MoS2 catalysts and reaction conditions on slurry phase hydrocracking of vacuum residue

The slurry phase hydrocracking (HCK) of vacuum residue (VR) in the presence of dispersed MoS2 catalyst was investigated under varying temperature, pressure, and reaction time. Extended X-ray absorption fine structure (EXAFS) measurements were used to obtain structural information about the dispersed MoS2 phase during the reaction. Under a standard reaction condition of temperature 673K and pressure 10.0MPa in an autoclave batch reactor, kinetic analysis for VR HCK confirmed that the reaction occurs in a parallel manner in the production of 77% liquid oils as major products such as vacuum gas oil and distillates with the generation of gas and of 23% coke in the presence of dispersed MoS2 catalyst (0.113mmol or 360ppm Mo). Although temperatures below 653K at 9.5MPa were found beneficial in coke reduction to less than 1.0wt.% in favor of hydrogenation at 33h of reaction, higher pressures over 15MPa at 673K were more influential in accelerating the VR conversion into liquid products, reaching 90% at 4h of reaction with coke reduction down to 1.2wt.% than the cases under conditions below 10MPa. Analysis of the spent catalysts by EXAFS and TEM demonstrated that the nanosized MoS2 phase was well developed from Mo(CO)6 in the early stage of the reaction, with lower MoS and MoMo coordination verifying the small MoS2 particles having more exposed and defect sites as active phases.

Hydrocracking of vacuum residue with solid and dispersed phase catalyst: Modeling of sediment formation and hydrodesulfurization

Effect of dispersed Mo based catalyst on residual hydrocracking was investigated in this paper. The study was performed in an industrial scale hydrocracking unit with the average reactor temperature of 399–419°C and pressure of 18MPa. Vacuum residue from Ural crude oil was fed to the reactor. A sediment formation model was proposed with parameters sets for the regime with classical supported Ni-Mo/Al2O3 catalyst and for that with a combined system of supported and dispersed catalyst. Four process parameters were incorporated in the model equation: reaction temperature, hydrogen partial pressure, exothermic gain and hydrogen makeup to feed mass ratio. A decrease of the sediment formation with the application of dispersed Mo catalyst was observed, which results in higher Mo concentration in the liquid phase and thus in higher hydrogenation activity and stabilization of coke precursors. Hydrodesulfurization was also investigated and a sulfur distribution model was created with parameters for both regimes. The model contains three lumps with significant sulfur content: sulfur contained in the vacuum residue, sulfur contained in the vacuum gas oil and hydrogen sulfide. Application of the catalyst and increase of reaction temperature from 399–414°C to 414–419°C resulted in increase of average sulfur conversion in vacuum residue from 86.5% to 87.9%.

Preparation of the Natural Zeolite Based Catalyst for Hydrocracking Process of Petroleum Derived Atmospheric Residue

This research focused on preparation catalysts by natural zeolite for hydrocracking and to compare their catalytic reactivity with commercial catalyst. Clinoptilolite type natural zeolite of Tsagaantsav and paraffinic atmospheric residue of Tamsagbulag crude oil were used in this research. The Ni or Fe ion was loaded into the zeolite sample which was enriched and calcined previously, by ion exchange method. It is determined by X-ray diffraction analysis that structure of natural zeolite was not broken down during metal loading. The conversion of feedstock in hydrocracking, in with modified zeolite was used, was 22.5% higher than none catalytic process and 8.9% higher than commercial catalyst. It is proved that both of modified zeolite catalysts worked effectively as a catalyst in hydrocracking of atmospheric residue. Even so the contents of sulfur in middle and heavy fraction were 490 - 615 ppm, after hydrocracking with Ni/zeolite, Fe/zeolite catalysts. This result showed that the Ni/zeolite, Fe/zeolite catalysts were inactive at hydrodesulfurization, because the contents of sulfur in middle and heavy fraction were 370 - 478 ppmafter hydrocracking without catalyst. Process for sulfur removal is needed after hydrocracking with Ni/zeolite orFe/zeolite catalyst.

Exploratory Investigation for the Coking Behavior during Slurry-bed Hydrocracking of Coal Tar Atmospheric Residue

The coking behavior of coal tar atmospheric residue (CTAR) during slurry-bed hydrocracking was studied. The CTAR hydrocracking was performed in the autoclave at 430 °C with H2 pressure of 13 MPa, comparing with that of the Merey atmospheric residue (MRAR). The properties of C7-asphaltene and toluene-insoluble in feedstocks and products were analyzed respectively to describe the CTAR coking behavior during slurry-bed hydrocracking. The experimental results showed that CTAR with higher asphaltene content (30 wt%) produced less amount of coke than MRAR with asphaltene content (9.29 wt%), and little coke on the inner surface of reactor was found. The toluene-insoluble in the feedstock contained the larger carbonaceous particles (about 7 μm) and the inorganic fine particles (about 1 μm). Both sulfurized catalyst particles and inorganic fine particles in CTAR provided independent condensation nuclear or growth nuclear for macromolecular radicals during slurry-bed hydrocracking. These particles promoted the disp...

Hydrocracking of vacuum residue using NiWS(x) dispersed catalysts

In this study, unsupported nickel-tungsten sulfide (NiWS(x)) particles, where x is the actual molar ratio of Ni/W (x=0, 0.005, 0.01, 0.02), were prepared, characterized with XRD, XPS, TEM, and EDX elemental mapping, and applied as a dispersed catalyst for upgrading of extra-heavy oil into good-quality liquid products. The hydrocracking reaction of vacuum residue (VR) was carried out at 400°C with an initial H2 pressure of 70bar. It was found that an increase in the Ni content increases the degree of sulfidation of tungsten, promotes formation of Ni-W-S phases, and enhances the overall catalytic activity. Among the NiWS(x) dispersed catalysts, the NiWS(0.02) catalyst showed the highest performance in total liquid product yield (87.0wt.%), commercial fuel fraction yield (51.9wt.%), API gravity value of liquid product (14.3°), and sulfur removal conversion (86.5%). In addition, coke formation (4.0wt.%) was efficiently suppressed, and the C5-asphaltene conversion (81.8%) was significantly raised.

Surface Modification of Nickel Sulfide Nanoparticles: Towards Stable Ultra‐Dispersed Nanocatalysts for Residue Hydrocracking

AbstractUltra‐small nickel sulfide nanoparticles (NSNPs) of 5–8 nm are prepared by a reverse microemulsion route and then modified by oleic acid and 1‐dodecanethiol to replace the adsorbed surfactant. Experimental results reveal that the particle size and crystal structure of the NSNPs did not change significantly during the modification process. Different from the adsorption by the electrostatic attraction between the surfactant and NSNPs, oleic acid and 1‐dodecanethiol are adsorbed firmly on the NSNPs through chemisorption. Catalytic hydrocracking tests demonstrate that the surface modification enhances the hydrocracking activity of the NSNPs. The surfactant‐coated NSNPs disperse in toluene‐insoluble products in as agglomerates of 20–30 nm, whereas the modified NSNPs mainly disperse as their original size. The results prove that the chemisorption of oleic acid and 1‐dodecanethiol on NSNPs remains steady and maintains the stable dispersion of NSNPs under high temperature and pressure.

Slurry Phase Hydrocracking of Residue by Phosphomolybdic and Phosphotungstic Acids

Slurry phase hydrocracking of vacuum residue was studied on heteropoly acids and on super acid. In this regards, heteropoly acid of phosphomolybdic, phosphotungstic and superacid of molybdenum-antimony fluoride were used. Deep hydrocracking of residue was noticed even at moderate operating conditions for all acidic catalysts. Due to higher hydrogenating functionality of tungsten, the HDM activity of the phosphotungstic acid is higher than that of molybdenum containing acids. Even the residue hydrocracking activity of former catalyst is also high. It is also noticed from sulphur distribution of liquid product that thiophenic sulphur compounds are formed due to C-S bond cleavage at branching of condensed aromatic rings. Moreover, phosphotungstic acid gives high percentage of aromatic products whereas the considerable amount of saturate hydrocarbons is produced by phosphomolybdic acid. The coke produced by phosphotungstic acid catalyst is hard in nature indicating that extensive polymerization reaction occurs at reaction conditions. Higher H/C ratio indicates the deep hydrogenation of liquid products in presence of super acids. Instead of use superacid, tungsten based heteropoly acid can be effectively used for hydrocracking of residue.

No.17 キュリー・ポイント・パイロライザー法を用いたゼオライト-アルミナ複合担体担持NiMo触媒による水素存在下での常圧残油の水素化分解(重質油・バイオマス・コプロセッシング(2))

No.17 キュリー・ポイント・パイロライザー法を用いたゼオライト-アルミナ複合担体担持NiMo触媒による水素存在下での常圧残油の水素化分解(重質油・バイオマス・コプロセッシング(2))

Effects of the Temperature and Initial Hydrogen Pressure on the Isomerization Reaction in Heavy Oil Slurry-Phase Hydrocracking

Thermal hydrocracking and slurry-phase hydrocracking of Karamay vacuum residue (KLVR) were studied, and the hydrocracked products were analyzed by gas chromatography (GC) and a paraffins, olefins, naphthalenes, and aromatics (PONA) composition analysis system. The effects of the temperature and initial hydrogen pressure on the isomerization reaction in heavy oil slurry-phase hydrocracking were investigated. Experimental data revealed that the conversion of KLVR increased as the temperature and initial hydrogen pressure increased in both thermal hydrocracking and slurry-phase hydrocracking. Hydrogen consumption of slurry-phase hydrocracking increased with the increase of the temperature and initial hydrogen pressure, while hydrogen consumption in thermal hydrocracking was negligible. Two impact indexes RG′ and RN′ were proposed to study the isomerization reaction in heavy oil slurry-phase hydrocracking. The results indicated that a high temperature and high initial hydrogen pressure enhanced the isoparaffi...

Effect of Sodium Dodecyl Benzenesulfonate on the Coke Formation during Slurry-Bed Hydrocracking of an Atmospheric Residue from Karamay

The effect of sodium dodecyl benzenesulfonate (SDBS) on the coke formation during slurry-bed hydrocracking of an atmospheric residue from Karamay (KAR) was studied, and three other kinds of surfactants, dodecyl trimethylammonium bromide (DTAB), oleic acid (OA), and coconut amine (CA), were used to compare to SDBS to deduce the reason for SDBS restraining the coke formation. The functional groups on the asphaltene surface and the effects of surfactants on the mean particle diameter of the catalyst, colloidal stability of the reaction system, and adsorptivity of asphaltene were investigated to find the reason for surfactant restraining the coke formation. The results showed that the order of reducing the total coke yield was CA > SDBS > OA ≈ none > DTAB and the order of reducing the coke on the reactor surface (cokesur) was SDBS > OA ≈ none > CA > DTAB. SDBS was the best surfactant to restrain coke formation during slurry-bed hydrocracking of KAR. The effects of surfactants on the colloidal stability of the reaction system were in accordance with the effects of surfactants on the total coke yield, and the effects of surfactants on the adsorptivity of asphaltene were in accordance with the effects of surfactants on cokesur, which meant that SDBS strengthening the colloidal stability of the system and lengthening the induction period of coking were important factors to reduce the total coke yield and restraining the adsorption of asphaltene on the reactor surface is the key factor to reduce cokesur. The analysis of X-ray photoelectron spectroscopy (XPS) data shows that KAR asphaltene is basic and SDBS has an acidic functional group and a suitable straight alkane chain length, making SDBS react with the basic KAR asphaltene particle to realize the effects on the colloidal stability of the reaction system and the adsorptivity of KAR asphaltene.

Effect of the textural parameters of the carrier and the preparation procedure of the supported Ni-Mo/Sibunit catalysts on their catalytic activity

The results of studies on the preparation of Ni-Mo sulfide catalysts based on a carbon-carbon composite material of the Sibunit type for the hydrocracking of heavy petroleum residue are reported. The effects of the support texture and the conditions of catalyst preparation on catalytic activity in the model reactions of 1-methylnaphthalene and dibenzothiophene conversion were demonstrated.

Hydrocracking of atmospheric distillable residue of Mongolian oil

Many catalytic processes to refine heavy part of crude oil have attracted much interest due to declining reserves of light crude oils. This study focused on hydrocracking process of atmospheric distillable residue of Mongolian crude oil in the first time compared to those of other countries. Residue samples were hydrocracked with a commercial catalyst at 450°C, 460°C, 470°C for 2 h under hydrogen pressure of 10 MPa. The amount of residual fraction (350°C<BP) decreased to 9.4wt% by the hydrocracking of atmospheric distillable residue from Tamsagbulag crude oil. When the ME-AR was hydrocracked, the high consumption of hydrogen was related to the lowest H/C atomic ratio of feed atmospheric residue. The amount of liquid fractions (BP<350°C) including gaseous products increased from 45.4wt% to 89.2wt%, when the reaction temperature increased from 450°C to 470°C. The highest yield of the middle fraction for each sample was observed at temperature of 460°C. On the other hand, the effect of temperature on the yield of middle fraction was not so high as compared with the yields of other fractions. The contents of n-paraffins on midlle and heavy fractions of TB-AR, DQ-AR were similar, but ME-AR’s was around 2 times lower than other after hydrocracking runs.DOI: http://dx.doi.org/10.5564/mjc.v12i0.166 Mongolian Journal of Chemistry Vol.12 2011: 24-28

Hydrocracking of vacuum residue into lighter fuel oils using nanosheet-structured WS2 catalyst

In this study, we tried hydrocracking of vacuum residue into lighter liquid oils using dispersed colloidal catalysts composed of nanosheet-structured WS2 materials. The vacuum residue of API gravity=2.3° was used as a reactant and hydrocracking reactions were performed in an autoclave batch reactor under 400°C and the initial H2 pressure of 70bar. Both single and multi-layer WS2 nanosheet catalysts were tested and their activities were compared with those of bulk WS2 and MoS2 catalysts. The single-layer WS2, which was the highest in specific surface area (97.6m2/g) due to its smallest particle size, showed the best performances in commercial fuel fraction yield (45.4wt.%), C5-asphaltene conversion (75.3%), API gravity of liquid product (13.8°), and metal removal activity. To characterize the physicochemical properties of catalyst, various characterization techniques were applied, including transmission electron microscope (TEM), X-ray diffraction (XRD) and Brunauer–Emmett–Teller (BET) analysis. In addition, to assess the qualities of hydrocracking products, we carried out API gravity measurement, inductively coupled plasma-mass spectrometry (ICP-MS), and simulated distillation (SIMDIS) analysis.

Macroporous NiMo/alumina catalyst for the hydrocracking of vacuum residue

We prepared a macro-mesoporous NiMo/alumina catalyst by the introduction of macroporosity to an alumina support, and tested its catalytic performance in the hydrocracking of vacuum residue for the first time. In this reaction, the use of the macro-mesoporous NiMo/alumina catalyst clearly led to a more desirable product distribution-a higher liquid yield and lower gas yield-than a mesoporous NiMo/alumina catalyst. This indicates that the macro-mesoporous catalyst structure facilitated hydrogenation relative to the mesoporous catalyst; for the latter, hydrocracking was relatively dominant. N2 adsorption/desorption experiments confirmed that NiMo impregnation reduced the pore size and volume, as well as the surface area, implying that the NiMo phases were located inside the mesopores and macropores. Macroporosity in the alumina support played an important role in improving the accessibility of vacuum residue to the NiMo active sites located inside pores, which are responsible for hydrogenation. By promoting hydrogenation, the macro-mesoporous NiMo/alumina catalyst increased the liquid yield of the hydrocracking of vacuum residue.