Hydrocracking Of Heavy Oil Research Articles

A Commercial Reactor Simulation for the Slurry-Phase Hydrocracking of Heavy Oil with a Mineral Catalyst Using Distillation Lumps and SARA-Based Kinetic Models

A Commercial Reactor Simulation for the Slurry-Phase Hydrocracking of Heavy Oil with a Mineral Catalyst Using Distillation Lumps and SARA-Based Kinetic Models

Effect of feedstock properties on the kinetics of hydrocracking of heavy oils

The ability to predict changes in selectivity and quality of products of catalytic hydrocracking reaction is essential for the performance and economics of the process due to the variation in properties of the fractions derived from heavy crude oils. The influence of different hydrocarbon feedstocks on hydrocracking reaction kinetics was analyzed using detailed experimental data reported in the literature. A six–lump kinetic model in the presence and absence of diverse catalysts was used. For the predictions of the pseudocomponent yields using the estimated kinetic parameters, global average absolute error values less than 4.3 % concerning the experimental data were obtained. Clear trends are observed between the values of some reaction rate coefficients and properties of the diverse feedstocks. The analysis of the effect of feedstock properties on the kinetic parameters indicated that streams with high API and low H/C ratio have higher global reaction rate coefficients of vacuum residue conversion, observing an increase of up to three–fold the coefficient values concerning the rise of asphaltene content. The contents of carbon residue and sulfur influence the performance of certain reaction pathways and the production of coke for the different feedstocks studied and types of catalysts.

Slurry-Phase Hydrocracking of Heavy Oil with Bifunctional Catalysts In Situ Generated from Oil-Soluble Ionic Liquid and Mixed Metal Oxide

Slurry-Phase Hydrocracking of Heavy Oil with Bifunctional Catalysts In Situ Generated from Oil-Soluble Ionic Liquid and Mixed Metal Oxide

Preparation of Fe‐based magnetic‐core‐supported Co and Ni catalyst: application in viscosity reduction of heavy oil hydrocracking

AbstractBACKGROUNDHeavy oil has the characteristics of high viscosity and low American Petroleum Institute gravity, which makes it difficult to transport and produce. The key to efficiently utilizing heavy oil is reducing viscosity and improving quality. Hydroconversion has the advantages of viscosity reduction and decreased coke production, but it is difficult to separate nonmagnetic catalysts from the reaction system, which affects the industrial application.RESULTSA spherical Fe3O4 (74.71 emu g−1) and a chain FeFe2O3 (110 emu g−1) were prepared as magnetic cores, and coated with SiO2 and Al2O3 layers, respectively. The metal‐supported catalyst modified with Co and Ni show irregular and honeycomb‐shaped surfaces, and the magnetic saturation strength decreases to 24.91 and 14.63 emu g−1, but still possessing superparamagnetic properties, enabling the catalysts to be separated from the reaction mixture. Fe‐Fe2O3@SiO2@Al2O3@CoNi catalyst has the best viscosity reduction effect for Canadian oil sands asphalt residue at about 410 °C and 10 MPa hydrogen pressure. The viscosity of the liquid product decreased significantly from 56 600 to 135 mPa s at 50 °C, with a viscosity reduction of 99.8%.CONCLUSIONMagnetic catalyst prepared from chain‐like Fe‐Fe2O3 has an excellent honeycomb structure, which can provide increased active surfaces and exhibit improved viscosity reduction performance. This work provides a strategy for the recovery of heavy oil hydrogenation catalysts and is expected to play a key role in the practical application of heavy oil hydrogenation catalytic viscosity reduction. © 2023 Society of Chemical Industry.

Molecular transformation of heavy oil during slurry phase hydrocracking process: A comparison between thermal cracking and hydrocracking

To systematically investigate the reaction mechanism of heavy oil in the slurry phase hydrocracking process, comparative experiments of thermal cracking and slurry phase hydrocracking of a residual oil were carried out. The molecular composition of sulfur and nitrogen compounds in the feedstock and their products was comprehensively characterized by gas chromatography and electrospray ionization Orbitrap mass spectrometry. The participation of hydrogen makes the apparent cracking rate in hydrocracking process significantly lower than that in the thermal cracking process, leading to a more controllable cracking degree and higher liquid yield. Nitrogen- and sulfur-containing aromatics with high molecular condensation degree are the key refractory heteroatoms because of large steric hindrance. Aromatics with ring number over 4 have high saturation reactivity, as well as the exposed five-membered heteroaromatic rings. The mutual influence of cracking, aromatic saturation, and hydrodeheteroatom during hydrocracking were also discussed according to bulk properties and molecular composition. The results deepen the understanding of the complex reaction network and mechanism of heavy oil hydrocracking process from both thermal reaction and hydrogenation perspectives, which will be instructive for the catalyst design and the process optimization.

Changes in structural parameters of SARA fractions during heavy oil hydrocracking using dispersed catalysts

Most of the characterization of SARA fractions of heavy crude oils during hydrocracking reactions is focused only on asphaltenes, and scarce works are devoted to analyze the differences in the structural parameters of all SARA fractions. In this work, a heavy crude oil is upgraded by non-catalytic and catalytic hydrocracking in a batch reactor at low severity conditions (3.9 MPa H2 pressure, 380 °C temperature, 800 rpm stirring rate, and 4 h reaction time). Three ore catalysts (hematite, magnetite and molybdenite) and one analytical grade catalyst (iron oxide) are employed. After reaction, the upgraded oils are first distilled and then separated into SARA fractions by the ASTM D86-16a and ASTM D2007-11 methods, respectively. NMR (1H and 13C), FTIR and GPC analyses are used to characterize SARA fractions before and after hydrocracking. The hydrocracking products exhibited a reduction in the average molecular weight of all SARA fractions as function of the hydrogenation capacity of each catalyst in the following order: Fe2O3 (analytical grade) > Molybdenite > Hematite > Magnetite. The structural parameters of saturates fraction remains unchanged except for the production of small length aliphatic chains from heavier fractions. For aromatics, resins and asphaltenes fractions, the number of aliphatic carbons is reduced due to dealkylation reactions increasing their aromaticity. For resins and asphaltenes fractions, hydrogenation and ring opening reactions are also carried out. Mo-based catalyst is mainly aimed at the conversion of asphaltenes, while the Fe-based catalysts focused on the conversion of resins.

An oil-soluble precursor with strong feedstock adaptability and excellent product selectivity for heavy oil hydrocracking

The feedstock adaptability and product selectivity of catalyst are very important for heavy oil hydrocracking. Considering that the components of heavy oil are mainly composed of aromatic compounds and alkyl compounds, Mo aryl-alkyl-dithiophosphate (Mo-Ar/R) with both benzyl and n-butyl was efficiently prepared based on the preparation method of Mo dialkyl-dithiophosphate (Mo-R) with only n-butyl whose high hydrogenation activity has been proved to improve the structural similarity to feedstock. Fourier transform infrared (FTIR) analysis, elemental analysis and oil solubility study were carried out on Mo-Ar/R and Mo-R. X-Ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and polarized microscope were used to obtain the structural and morphological information of MoS2 catalysts. Mo-Ar/R and Mo-R were evaluated in the hydrocracking of atmospheric residue ultra heavy oil (feedstock A), high sulfur vacuum residue (feedstock B) and coal tar oil (feedstock C) at 430 ℃ with an initial hydrogen pressure of 7 MPa for various reaction times, respectively. The results showed that the coexistence of benzyl and n-butyl led to better oil solubility of Mo-Ar/R, smaller size, lower stacking number and shorter slab length of the resulting MoS2 catalysts. Compared with Mo-R, Mo-Ar/R increased the valuable product yields during hydrocracking of feedstock A, feedstock C and feedstock B by 1.33 wt%, 3.53 wt% and 3.97 wt%, decreased the coke yields by 0.21 wt%, 0.40 wt% and 0.51 wt% and decreased the gas yields by 0.65 wt%, 0.97 wt% and 1.19 wt%, respectively. The initial hydrogen consumption rates and TOFs obtained in the presence of Mo-A/R are higher than that obtained in the presence of Mo-R. The performance difference between Mo-Ar/R and Mo-R seemed to be related to the contents of saturates of the different feedstocks. The coexistence of benzyl and n-butyl was proved to lead to the better feedstock adaptability and product selectivity of Mo-Ar/R compared with Mo-R due to the better structural similarity.

Study into the effects of the feedstock properties and stability on the catalytic hydrocracking of heavy oil

Various heavy oil feedstocks were investigated using several methods that are commonly employed to evaluate the stabilities of such feedstocks. More specifically, the microcarbon residue (MCR) content, the colloidal instability index (CII), the stability index (SI), and the Heithaus parameter (P value) were employed. The catalytic hydrocracking of heavy oils was carried out in a slurry-phase semi-batch reactor at 410 °C under 110 bar of hydrogen and in the presence of a Mo-octoate precursor (1000 wppm). The correlation between the feedstock properties (i.e., the MCR content and the CII) and the reaction performance in the upgrading process was established. It was found that feedstocks with higher MCR contents also contained greater numbers of aromatic components and shorter alkyl side chains, resulting in a higher tendency for coke formation and a lower yield of de-asphalted oil (DAO). Stability evaluation showed that stable feedstocks tended to produce less coke, greater DAO yields, and lower amounts of impurities compared to unstable feedstocks. In addition, it was revealed that the CII was sensitive to the reaction performance, suggesting that improving the stabilities of asphaltenes by means of the solvency effect is the key to obtaining high product quality.

Estimation of the gas hold up and flow regime of a bubble column reactor for the slurry phase hydrocracking of heavy oil

This study investigated gas hold up and flow regimes according to operating conditions (temperature, pressure, superficial gas velocity) for the design of a slurry phase hydrocracking reactor for heavy oil. Heating medium oil, vacuum residue (VR) and hydrocracking products were used in a bubble column reactor which had a diameter of 0.05 m and a height of 2.3 m. The results confirmed that the gas hold up increased and the flow regime transition point was delayed as VR was converted to a hydrocracking product (change in physical properties), and pressure also affected the flow regime transition. Using the dynamic gas disengagement method, the flow regime transition was observed in the actual hydrocracking reaction, and at the same time, it was confirmed that the hydrocracking reaction performance decreased. A VR slurry phase hydrocracking flow regime map is proposed by modifying the existing correlations, and a guide for reactor design and operation is suggested.

Experimental Investigation of Metal-Based Calixarenes as Dispersed Catalyst Precursors for Heavy Oil Hydrocracking

Slurry-phase hydrocracking utilizing metal-containing oil-soluble compounds as precursors of dispersed catalysts is an effective approach for heavy oil upgrading. We propose applying metal-based p-tert-butylcalix[6]arene (TBC[6]s) organic species as dispersed catalyst precursors to enhance catalytic hydrogenation reactions involved in the upgrading of vacuum gas oil (VGO). Co- and Ni-based TBC[6]s were synthesized and characterized by SEM-EDX, ICP, XRD, and FT-IR. The thermogravimetric and calorimetric behaviors of the synthesized complexes, which are key properties of dispersed hydrocracking catalysts, were also explored. The experimental evaluation of the synthesized catalyst precursors show that the synthesized metal-based TBC[6] catalyst precursors improved the catalytic hydrogenation reactions. A co-catalytic system was also investigated by adding a commercial, first-stage hydrocracking supported catalyst in addition to the dispersed catalysts. The naphtha yields increased from 10.7 wt.% for the supported catalyst to 11.7 wt.% and 12 wt.% after adding it along with Ni-TBC[6] and Co-TBC[6], respectively. Mixing the metal-based precursors resulted in elevated yields of liquid products due to the in situ generation of highly active Co–Ni bimetallic dispersed catalysts.

Analysis of kinetic models for hydrocracking of heavy oils for In-situ and Ex-situ applications

In-situ processing has been suggested as an alternative for upgrading heavy oils and bitumen directly in the reservoir. However, there is not much information on the kinetic of the reactions occurring during this process. In this work, all the kinetic models reported so far for the in-situ and ex-situ upgrading of heavy crude oil or residue using nanocatalyst and hydrogen are discussed. Most of the kinetic models are based on the lumping approach and assume a first-order of reaction. The approaches used to calculate the kinetic parameters do not ensure reaching the global minimum of the objective function to determine their optimal values. The lowest energy demanding reactions for the hydrocracking of residue, vacuum gasoil, and distillates are in series as reported by almost all kinetic models. The calculated activation energies agree that gas fraction is only formed by residue conversion, and reactions are mainly carried out in series rather than in parallel under the studied conditions.

Trialkylmethylammonium molybdate ionic liquids as novel oil-soluble precursors of dispersed metal catalysts for slurry-phase hydrocracking of heavy oils

Slurry-phase hydrocracking is an effective technology for the conversion of heavy oils to clean and light fuels. Herein, trialkylmethylammonium molybdate ionic liquids (ILs) with multiple long-chain alkyl groups were designed, and applied as the oil-soluble precursors of dispersed metal catalysts for slurry-phase hydrocracking. The molybdate ILs were synthesized through a two- or three-step route from readily available reagents under mild conditions. The chemical structure and sulfidation behavior of molybdate ILs were characterized first. The performance of molybdate ILs for hydrogenation was then evaluated with phenanthrene as the model compound. The dispersed MoS2 catalysts in-situ produced in the model system were isolated and characterized to explain the different performance of oil-soluble precursors. The performance of molybdate ILs for slurry-phase hydrocracking of heavy oils was finally investigated. To figure out the favored routes for the conversion of heavy oils, the reaction rate constants were also calculated based on an established kinetical model.

Value-added materials recovered from waste bone biomass: technologies and applications.

As the world population increases, the generation of waste bones will multiply exponentially, increasing landfill usage and posing health risks. This review aims to shed light on technologies for recovering valuable materials (e.g., alkaline earth material oxide such as CaO, hydroxyapatite, beta tri-calcium phosphate, phosphate and bone char) from waste bones, and discuss their potential applications as an adsorbent, catalyst and catalyst support, hydroxyapatite for tissue engineering, electrodes for energy storage, and phosphate source for soil remediation. Waste bone derived hydroxyapatite and bone char have found applications as a catalyst or catalyst support in organic synthesis, selective oxidation, biodiesel production, hydrocracking of heavy oil, selective hydrogenation and synthesis of bioactive compounds. With the help of this study, researchers can gather comprehensive data on studies regarding the recycling of waste bones, which will help them identify material recovery technologies and their applications in a single document. Furthermore, this work identifies areas for further research and development as well as areas for scaling-up, which will lead to reduced manufacturing costs and environmental impact. The idea behind this is to promote a sustainable environment and a circular economy concept in which waste bones are used as raw materials to produce new materials or for energy recovery.

Estimation of the Gas Hold Up and Flow Regime of a Bubble Column Reactor for the Slurry Phase Hydrocracking of Heavy Oil

Estimation of the Gas Hold Up and Flow Regime of a Bubble Column Reactor for the Slurry Phase Hydrocracking of Heavy Oil

Facile synthesis of magnetic recyclable Fe3O4@PDA@MoS2 nanocomposites for effectively hydrocracking of residue

Magnetic nanocomposites provide manifold perspectives for sustainable development. However, the cumbersome operation process and energy consumption after treatment limit its application in the practical industry. Herein, we present a simple and universal strategy to synthesize Fe3O4@PDA@shell nanoparticles via in-situ homogeneous hydrolysis reaction growth different nanomaterials on the PDA modified Fe3O4 nanospheres, which can avoid multistep repetitive washing, redispersing, and drying. As an example, we introduced the synthesis process of Fe3O4@PDA@MoS2 catalyst used for heavy oil hydrocracking in detail. The synthesis processes were significantly simplified and the dispersity and stability of the nanosized MoS2 were improved due to the copious functional groups and strong adhesion properties of polydopamine. The as-prepared Fe3O4@PDA@MoS2 nanoparticle catalysts showed high activity and excellent stability. The viscosity of residue was decreased by 99.8% and the recovery of the catalyst reached 90% under harsh conditions (405 ℃ at 13 MPa H2). We also demonstrate the versatility of this strategy for other shell materials, such as WS2, VS2, Pd, and Rh components, which is promising for designing multifunctional core−shell−shell materials for various applications.

Ligand structure effect in oil-soluble phosphorus-containing molybdenum precursors for slurry-phase hydrocracking of heavy oil

Slurry-phase hydrocracking for heavy oil upgrading is a challenging technology in the petroleum refining industry. We prepared various P-containing Mo precursors to elucidate the effect of their ligand structures on the slurry-phase hydrocracking of vacuum residue. Characteristic analyses of the Mo precursors were performed by first determining their dispersibility and decomposition patterns, followed by evaluating the sulfidation degree and morphology of the resulting MoS2 catalyst. The dispersibility of the Mo precursors was evaluated by a method of measuring the solubility parameter based on the oil compatibility model. The slurry-phase hydrocracking results revealed that the H2 consumption rate, residue conversion, hydrodesulfurization, and asphaltene conversion were dependent on the Mo precursor. The Mo triethylphosphite species, which had the largest number of active sites, was found to be the most efficient precursor for improving product distribution and product quality.

Enhancing the activity of MoS2/SiO2-Al2O3 bifunctional catalysts for suspended-bed hydrocracking of heavy oils by doping with Zr atoms

Developing catalysts with not only hydrogenation activity but also cracking activity is very important for the advancement of suspended-bed hydrocracking technology. Within this respect, MoS2/SiO2-Al2O3 bifunctional catalyst is a kind of typical catalysts with both hydrogenation and cracking activity. Herein, a series of Zr-doped SiO2-Al2O3 mixed oxides were synthesized by a sol-gel coupled with hydrothermal method. The synthesized mixed oxides were characterized for chemical structures and acidic properties. It is found that doping SiO2-Al2O3 with Zr atoms significantly increases the numbers of acidic sites. The Zr-doped SiO2-Al2O3mixed oxides were then combined with dispersed MoS2, which was in-situ produced from oil-soluble Mo precursors, to fabricate a novel kind of bifunctional catalysts for suspended-bed hydrocracking of heavy oils. Owing to the significantly increased numbers of acidic sites in Zr-doped SiO2-Al2O3 mixed oxides, corresponding bifunctional catalysts demonstrate much enhanced activity for suspended-bed hydrocracking of heavy oils in relative to MoS2/SiO2-Al2O3 bifunctional catalysts.

A new approach for synthesis of well-crystallized Y zeolite from bentonite and rice husk ash used in Ni-Mo/Al2O3-Y hybrid nanocatalyst for hydrocracking of heavy oil

A series of Ni-Mo/Al2O3-Y hybrid nanocatalysts were synthesized for hydrocracking of heavy oil. The well crystallized Y zeolite was synthesized from mineral bentonite and rice husk ash by a two-step synthesis method. The solution combustion method was applied to develop a fast and simple technique for preparing of alumina-supported NiMo catalyst with high hydrodesulfurization activity. Such activity may be due to the morphological and textural modification as a consequence of the release of a high amount of exhaust gases during the combustion process. The XRD analysis revealed that the P zeolite was a competitive phase presented in the obtained product that could be eliminated using a two-step synthesis method. Compared to a one-step method, the pore volume and external surface area of the synthesized zeolite by the two-step method increased by 74 and 62%, respectively. The hydrocracking results illustrated that the synthesized zeolite was able to convert 66% of heavy oil to lighter products and reduce the viscosity up to 60%. Furthermore, the amount of sulfur removal was found to be 58%. The spent catalyst characterization suggested that the type of deposited coke was hard coke with the unsaturated aromatic ring which could be responsible for the pores blockage after the cracking reaction.

Heavy oil hydrocracking kinetics with nano-nickel dispersed in PEG300 as slurry phase catalyst using batch reactor

The kinetics of slurry phase heavy oil hydrocracking with nickel nanoparticles dispersed in PEG300 as the slurry phase catalyst was investigated. Colloidal metal nanoparticles were synthesized using a chemical reduction method. Catalytic evaluations were performed in a batch reactor with 7.0 MPa H2 and varying temperatures (310–370 °C) and reaction times (4–72 h). A five-lump kinetic model was used to obtain kinetic parameters using the R software with the Levenberg-Marquardt nonlinear least-squares algorithm. The order of the residue hydrocracking reaction rate equation was 2.5. The activation energies were determined, and the calculated product compositions were in agreement with the experimental values (<5%). The residue exhibited high selectivity towards naphtha. High residue conversion was accomplished, even at low reaction times.

Reaction Kinetics Model for a Slurry Hydrocracking Process Using Limonite Catalyst

Kobe Steel, Ltd. and Chiyoda Corp. developed the KOBELCO Slurry Phase Hydrocracking (SPH) process for the ultimate heavy oil upgrading, both at upstream wells and refineries with a cracking rate higher than 90 %. Generally, with the heavy oil hydrocracking process, a higher cracking rate is associated with a greater sludge formation rate due to a radical reaction, large molecular condensation and polymerization induced by thermal cracking. This research objective is to apply optimized operation conditions, obtained through experimental results, to the new process system’s development for the pilot and commercial plants by achieving a more than 95 wt% VR cracking rate, more than 80 wt% of oil yield, and minimizing sludge generation. For this purpose, the reaction time, amount of limonite content, reaction pressure, and reaction temperature in the 1 L autoclave are tested to find the optimal reaction point. To scale up the SPH process to pilot plants and commercial plants, a new reaction model, for which reaction conditions are theorized, must be developed. This study proposes a new reaction model by simulating the autoclave tests, verifying its validity, and discussing future challenges and plans.