Light Cycle Oil Research Articles

Towards Bio-Crude Refinery Integration: Hydrodeoxygenation and Co-Hydroprocessing with Light Cycle Oil

Hydrothermal liquefaction of solid waste has been gaining more and more attention over the last few years. However, the properties of the HTL product, i.e., biocrude, are limiting its direct utilization. As a result, HTL biocrude upgrading is essential to improve its quality. The main objective of the current research is to study the hydrotreatment stabilization of HTL biocrude, produced from spent coffee grounds, utilizing commercial hydrotreated catalysts, and also to investigate the integration of the stabilized biocrude into a light cycle oil (LCO) hydrotreatment plant for coprocessing to target hybrid fuel production. The results have shown that hydrotreatment is a very promising technology that can successfully remove the oxygen content from raw biocrude by hydrodeoxygenation, decarbonylation and decarboxylation reactions, leading to a stabilized product. The stabilized product can be easily blended with the LCO stream of a typical refinery, leading to the production of jet and diesel boiling range hydrocarbons, favoring at the same time the hydrogen consumption of the process. The findings of this manuscript set the basis for future research targeting the production of renewable advanced biofuels from HTL biocrude from municipal waste.

Investigation on the Hydrothermal Condition in Synthesis of Active Matrix from Metakaolin: Physicochemical Properties and Intrinsic Cracking Activities

The current trends in research and development of FCC catalyst is focused on the formulation of active matrices that serve as pre-crackers, with the objective of reducing the diffusional resistance of the longer chain hydrocarbon molecule in the feed. In this study, an aluminosilicate active matrix was synthesised from metakaolin using hydrothermal method. The experimental variables that were varied were hydrothermal temperature, in the range of 80 to 110 °C, and hydrothermal time, in the range of 12 to 72 hours, to investigate the best conditions for synthesising the active matrix. Subsequently, the active matrix was subjected to a series of analyses, including X-ray fluorescence, X-ray diffraction, N2 physisorption, NH3-temperature programmed desorption, Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetry, with the objective of determining its composition, crystal characteristics, surface characteristics, acidity, functional groups, material structure, and thermal characteristics. Additionally, the active matrix was tested for its intrinsic cracking activity using the micro activity test (MAT). The results indicate that the best temperature for hydrothermal synthesis of the active matrix is 80 °C. The active matrix synthesised with a heating time of 24 hours demonstrated the highest light cycle oil yield, reaching 38.9 wt%. Meanwhile, the active matrix synthesised at 48 hours exhibited the most favourable characteristics, with a specific surface area of 144.23 m2/g and a pore volume of 0.9933 cm3/g, as well as the highest cracking conversion of 70.0 wt%. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Evaluation of soot emission and wall heat loss for the fuels with high aromatic contents using the coupled analysis of chemical luminescence images with heat flux

The stricter regulations on the sulfur content of marine fuel oil in the general sea area that came into effect in January 2020 have led to a prediction of the increase of light cycle oil with high aromatic contents. The higher aromatic content is expected to result in higher soot in the exhaust gas. During combustion, soot emits radiant heat because of blackbody radiation, some of which passes through the walls of the combustion chamber and is released outside. Therefore, the exhaust emission characteristics and wall heat loss are affected if soot formation during combustion differs depending on the aromatic content of the fuel oil. This study developed an analytical method that combines the temporal and spatial distributions of C2 and OH radicals (these species contribute to soot formation and oxidation) to evaluate the emission and wall heat loss characteristics of different aromatics in fuel oils via combustion and heat flux analysis. The method was applied to test fuels containing different aromatic contents. Two test fuels containing 60 vol% each of toluene (monocyclic) and 1-methylnaphthalene (bicyclic) were evaluated in a rapid compression machine with a 100 mm wall-to-wall distance combustion chamber. The results suggested that the differences in soot emissions were observed because of differences in aromatics, and no differences in the wall heat flux were observed. The distributions of C2 and OH radical luminescence intensities between the walls were examined, and the differences in soot production were attributed to differences in the C2 radical production upstream of the flame in the region of low air entrainment. The lack of difference in the heat flux between the test fuels can be attributed to the the differences in the C2 and OH luminescence intensities, which are related to the heat release rate and heat flux, being almost nonexistent near the walls.

Sustainable Liquid‐Organic‐Hydrogen‐Carrier‐Based Hydrogen‐Storage Technology Using Crude or Waste Feedstock/Hydrogen

For liquid organic hydrogen carrier (LOHC) technology to be competitive with other H2‐storage methods, it is crucial to reduce the cost of LOHC materials occupying the high proportion of the embodied energy required for system implementation. Promising approaches are to convert crude or waste feedstock into LOHC materials and to utilize crude hydrogen sources obtained from various routes. Thus, in this review, the state‐of‐the‐art advances in sustainable LOHC‐based hydrogen storage using crude or waste feedstock, associated with their conversion into LOHC materials, and coupling crude hydrogen with LOHC system to obtain high‐purity H2 without separation and purification are highlighted. Petroleum sources like light cycle oil and pyrolysis fuel oil are used after liquid–liquid extraction, combined distillation/hydroprocessing, and one‐pot hydrotreating–hydrocracking. In case of converting renewable resources (e.g., biomass and plastic waste), depolymerization followed by hydrodeoxygenation is an effective approach. To utilize crude hydrogen sources for hydrogen storage, catalysts should be designed and synthesized toward activating LOHC hydrogenation reaction at lower temperatures, along with high CO resistance. Consequently, this context provides guidance for the development of LOHC technology to accelerate its commercialization.

Catalyst for moderate hydrocracking of polycyclic aromatic hydrocarbons in LCO to produce chemical raw materials: Ni in-situ modified Y zeolite-supported-NiWS

Light cycle oil is rich in polycyclic aromatic hydrocarbons with low cetane number, and the best approach is to convert them into chemical raw materials with carbon number in the range of C6-C8. In view of the above problem, Y zeolites with different Ni contents were synthesized by in-situ synthesis strategy, and corresponding NiWS supported catalysts were prepared. Taking naphthalene as the model compound, the catalytic performance of the catalysts was evaluated. The effects of Ni in-situ modification on the physicochemical properties of Y zeolite and the active phase properties of catalyst were investigated. Ni in-situ modification effectively improved the number of medium-strong B acid sites in Y zeolite and weakened the MSI of the catalyst. Appropriate Ni content had a positive effect on the dispersion and stacking number of active phase. Owed to the increased number of medium-strong B acid sites and the properties of active phase, 2J-Ni-YCat showed the best catalytic performance in the hydrocracking of naphthalene to produce C6-C8 products. It is expected to provide reference for the transformation of polycyclic aromatic hydrocarbons into high value-added C6-C8 products in petrochemical industry.

Investigation of the Effect of Silica and Phosphorus Content on the Performance of Active Matrix as Component of Cracking Catalyst

Fluid catalytic cracking (FCC) is a technique that converts heavy-fraction feed into fuel. The FCC catalyst components consist of a composite material made of zeolite, filler, binder, and an active matrix. The active matrix is used as a pre-cracker for the heavy-fraction feed. This study examined the impact of the Si/Al ratio and the addition of phosphorus on the physical properties and activity of the active matrix. The synthesis technique refers to US patent 6723297 B2. The utilized variants consisted of SiO2 ranging from 50 to 80 weight percent and a phosphorous addition ranging from 1 to 2 weight percent. The physical characteristics of the active matrix were assessed using nitrogen physisorption and NH3-Temperature programmed adsorption/desorption techniques. A chemical activity test was conducted using the micro activity test (MAT) method, with vacuum gas oil (VGO) as the feedstock. This test was done in accordance with the ASTM D 5154 – 03 standard. The results indicated that the silica composition in the active matrix is directly related to the average pore diameter but inversely related to the specific surface area. Additionally, the inclusion of phosphorus had a similar impact. The silica-alumina-phosphorous variant containing 75%-wt of SiO2 exhibited the most superior active matrix activity, achieving the maximum acquisition of light cycle oil (LCO) at 33%-wt.

Hydrocracking of a HDPE/VGO Blend: Influence of Catalyst-to-Feed Ratio on Fuel Yield and Composition

The effects that the catalyst-to-feed ratio have on the yields of products and composition of the naphtha and light cycle oil (LCO) fractions in the hydrocracking of a blend composed of high-density polyethylene (HDPE) and vacuum gasoil (VGO) using a PtPd/HY catalyst were assessed. The hydrocracking runs were carried out in a batch reactor fixing the following operation conditions: 420 °C, 80 bar, 120 min and an HDPE-to-VGO ratio of 0.2 gHDPE gVGO−1, varying the catalyst-to-feed mass ratio within the 0.05–0.1 gcatalyst gfeed−1 range. The obtained results exposed that a catalyst-to-feed mass ratio of 0.075 gcatalyst gfeed−1 provided the best results, since the conversion of the heavy cycle oil (HCO) fraction and of the HDPE offered quite high values (73.1 and 63.9%, respectively) without causing an excessive overcracking in the form of gas products (the yield of gases was of 25%). Moreover, an interesting yield of naphtha (37.0 wt%) with an RON within the commercial standards (92.5) was obtained. With regard to coke formation, not-so-developed structures were formed for a catalyst-to-feed mass ratio of 0.075 gcatalyst gfeed−1, easing their combustion and presumably extending the lifespan of the catalyst.

Impact of Metal Impregnation of Commercial Zeolites in the Catalytic Pyrolysis of Real Mixture of Post-Consumer Plastic Waste

This work reports the study of the catalytic pyrolysis of rejected plastic fractions collected from municipal solid waste whose mechanical recovery is not plausible due to technical or poor conservation issues. The chemical recycling using catalytic pyrolysis was carried out over commercial zeolites formulas, i.e., HY and HZSM-5, in which Ni or Co metals were deposited at two different loadings (1 and 5%, wt.). The presence of these transition metals on the zeolitic supports impacted the total production of compounds existing in the liquid oil. The samples were characterized in terms of structural, chemical, and morphologic properties, and the production of different fuel fractions (gasoline, light cycle oil, and heavy cycle oil) was correlated with a combined parameter defined as a ratio of Acidity/BET area.

Co-processing of organic fraction from groundnut shell biocrude with VGO in FCC unit to produce petrochemical products

This research work explores the transformative potential of biomass leading to sustainable production of biocrude and its utilization in refinery and petrochemical sector for reducing reliance on fossil fuels. In this study, groundnut shell biomass was thermally converted in a customized continuous semi pilot auger reactor in temperature range of 400–700 °C. The optimum temperature for maximizing biocrude was studied, and detailed chemical analysis revealed that biocrude contains hydrocarbons and alcohols with a calorific value of 29 MJ/kg. Furthermore, this study demonstrates the performance of the FCC (Fluid Catalytic Cracking) catalyst and feedstock (H-T- VGO (Hydrothermal vacuum gasoline oil) & Biocrude) in a laboratory-scale utilizing ACE R + MM (Advanced Cracking Evaluation - Residue and Metals Management) unit under predetermined temperatures (515 °C, 525 °C) and a fixed cat-to-oil weight ratio (CTO = 6 w/w). The organic phase and FCC feedstock in different weight ratios from 5 to 20 wt % were blended. There are marginal changes in the yields of dry gas, LCO (light cycle oil) and HCO (heavy cycle oil), with significant increase in the yields of LPG (liquified petroleum gas) and gasoline. Bottoms have been reduced, and coke formation has been adjusted. However, this process requires prudent blending and temperature choices, with future recommendations including improvement in the quality of biocrude to enhance the yields of both LPG and gasoline along with reduced coke formation.

Production of Fuel Oil from Blends of Refinery Products for Powering Heat Exchanger

Fuel oil, also known as furnace oil is a fraction of crude oil obtained when distillation processing is carried out in the refinery. Due to the high viscous of the heavy fuel oil, that makes it difficult to be pump throughout the pipework of the power plant, it is necessary to produce a fuel oil that will meet up the required standard. The aim of this study was to produce fuel oil from the blend of refinery intermediate product which meet certain European fuel specifications outlined in the EN 590:2009 standard alongside NMDPRA Standards. The blending stocks obtained from the Warri Refinery and Petrochemical Company (WRPC) were first filtered to remove some particulate impurities before they were analyzed to determine their properties after which, they were introduced into a mixed-tank that has an agitator connected and the blending was done using the blending ratio obtained from literature. The fuel oil produced was eventually analyzed for properties such as: Specific Gravity, API Gravity, Density, Viscosity, Kinematic Viscosity, Moisture Content, Flash Point, Cloud Point, Pour Point and Sulphur content. The sample with a composition of 33.3% of Decant oil (DCO), 33.3% Heavy gas oil (HGO), 33.3% light cycle oil (LCO) produced fuel oil of specific gravity 0.916, API Gravity 22.95, Density 0.896, Viscosity 40, Kinematic viscosity 4.7, pour point -6.5 and flash point 109, The analysis of the fuel oil meet the standard for blended fuel oil, according to the ISO 8217:2017 Standard. The results confirmed that blending of decant oil with conventional petroleum diesel (heavy and light gas oil) has a highly significant effect on the properties of the resulting fuel blend. The results show that by increasing the heavy gas oil content of the blend, the flash point of the blend increases; while increasing the decant oil content of the blend results in a decrease in Cloud point. The results of the analysis of the produced fuel oil confirms that its properties fall within the acceptable range for Fuel Oil and can be used as fuel for fired heaters and furnaces of the refinery and other process plants.

Dominant role of zeolite in coordination between metal and acid sites on an industrial catalyst for tetralin hydrocracking

An effective approach for upgrading light cycle oil (LCO) is the targeted conversion of poly-aromatic hydrocarbons to valuable monoaromatic hydrocarbons.

Effect of temperature, hydrogen donor, and zeolites on light cycle oil cracking: thermodynamic, experimental, and DFT analyses

Experimental, thermodynamic, and DFT analyses determine optimal conditions for maximizing BTX yields from LCO and provide mechanistic insights.

Artificial Intelligence for Hybrid Modeling in Fluid Catalytic Cracking (FCC)

This study reports a novel hybrid model for the prediction of six critical process variables of importance in an industrial-scale FCC (fluid catalytic cracking) riser reactor: vacuum gas oil (VGO) conversion, outlet riser temperature, light cycle oil (LCO), gasoline, light gases, and coke yields. The proposed model is developed via the integration of a computational particle-fluid dynamics (CPFD) methodology with artificial intelligence (AI). The adopted methodology solves the first principle model (FPM) equations numerically using the CPFD Barracuda Virtual Reactor 22.0® software. Based on 216 of these CPFD simulations, the performance of an industrial-scale FCC riser reactor unit was assessed using VGO catalytic cracking kinetics developed at CREC-UWO. The dataset obtained with CPFD is employed for the training and testing of a machine learning (ML) algorithm. This algorithm is based on a multiple output feedforward neural network (FNN) selected to allow one to establish correlations between the riser reactor feeding conditions and its outcoming parameters, with a 0.83 averaged regression coefficient and an overall RMSE of 1.93 being obtained. This research underscores the value of integrating CPFD simulations with ML to optimize industrial processes and enhance their predictive accuracy, offering significant advancements in FCC riser reactor unit operations.

Selective Single‐step Co‐hydroprocessing of Light Cycle Oil and Waste Cooking Oil Mixtures for Diesel Fuel Production

AbstractThis study investigates the co‐hydroprocessing of light cycle oil (LCO) with waste cooking oil (WCO) as a potential strategy to enhance LCO′s qualities and overall performance. The study involves the integration of LCO with WCO in three different ratios, facilitating a combined hydrotreatment process within a fixed bed continuous down‐flow reactor. The findings reveal that incorporating WCO into LCO hydrotreatment enhances LCO′s properties, albeit with a minor reduction in hydrodesulfurization efficacy. WCO demonstrates approximately 10.7 % density and 26 % cetane number improvements compared to the LCO/WCO (70/30) blend at 380 °C. The most significant reduction in di and poly‐aromatic compounds is observed at 340 °C for pure LCO, while WCO inclusion has minimal impact on poly‐aromatic saturation. The yield range for medium distillates across all products is between 87 % and 93 %. The time‐on‐stream study suggests excellent catalyst stability and activity up to 456 h, which is one of the highest lifetimes reported so far. TGA study of the spent catalyst indicates 22 wt % coke deposition complemented by TEM results. FTIR analysis revealed absorptions of alicyclic hydrocarbons‐type compounds deposited over the catalyst surface. This research contributes to the development of innovative catalysts for selectively converting LCO and WCO into diesel‐range hydrocarbons through single‐step process.

Selective cracking of light cycle oil to monoaromatics over non-noble bifunctional zeolite-supported Ni and NiW catalysts

The utilization of light cycle oil (LCO) for producing monoaromatics is investigated using bifunctional Ni and NiW catalysts supported on four different zeolites at atmospheric pressure without using external H2. The order of BTX yield for various feed compositions (2-methylnaphthalene, 2-methylnaphthalene + 9-methylanthracene, LCO) is: NiW/Beta > NiW/Y > Ni/Beta > NiW/Mordenite > Ni/Y > NiW/Mix > Ni/Mordenite > Ni/Mix, whereas the coke yield exhibits the reverse trend. The better performance of NiW-based catalysts is explained by the formation of NiW oxide species and their strong interactions with the support, as ascertained through H2-TPR, XPS, and UV-DRS. The higher moderate acidity, optimal balance between medium-strength Brønsted acid sites (BAS) and strong Lewis acid sites (LAS), and the higher hydrogen transfer index (HTI) in NiW-based catalysts, facilitate the selective cracking of LCO, resulting in the desired product yield. This study also establishes a strong correlation between the structural properties of various catalysts (pore diameter, surface area, pore volume, crystallite size) and the performance parameters, thus explaining the superior performance of Beta zeolite-supported catalysts for BTX production. Experiments with NiW/Beta and a physical mixture of W/Beta and Ni/Beta show the synergistic effect due to the co-presence of Ni and W. It is inferred that triaromatics are rapidly transformed to diaromatics, and the conversion of monoaromatics having two rings determines the BTX yield. LCO compounds are found to be the primary source for the formation of monoaromatics, while n-hexadecane (n-HD) is the hydrogen source. Reaction pathways for 2-methylnaphthalene and 9-methylanthracene conversion are presented based on detailed product characterization.

Study of aromatic extraction from light cycle oil from the viewpoint of industrial applications

Light cycle oil (LCO) is a significant products of fluid catalytic cracking (FCC) process in refineries. Increasing the output of high-value chemicals from LCO is an important step towards achieving ‘dual carbon’ targets. Separating aromatic and non-aromatic components in LCO is crucial to producing valuable products. Extraction is a promising process for separating these components based on the principle of “polar similarity and solubility”. From the perspective of industrial applications, this study explores the development and application of novel functionalized extractants to produce valuable products. Ionic liquids (ILs) with alkyl-substituted imidazoles [CnMIM]+ and alkyl-substituted pyridines [CnMPy]+ as cations and tetrafluoroborate [BF4]− and hexafluorophosphate [PF6]− as anions were used. The effects of extraction temperature, IL-oil ratio, number of extraction stages, and reusability were systematically investigated. In addition, the basic physical properties data of ILs and residues in oil were studied in detail. The suitability of ionic liquids for industrial applications was evaluated based on their solubility with hydrocarbons, physical and chemical properties, selectivity for aromatics, and residues in oil. Following a thorough examination of the performance of ionic liquids for the extraction of aromatics from LCO, [C6MIM][PF6] was identified as the most suitable extractant. A multi-stage countercurrent extraction process was established and the conditions systematically studied. The results demonstrate that the aromatic content of the extracted oil is greater than 95 wt%, which can be utilized for producing BTX products. Meanwhile, the aromatic content of the raffinate oil is less than 10 wt%, which can function as a clean diesel blending component or as steam cracking feedstocks. This study has successfully promoted the industrial application of functionalized ionic liquids for the LCO dearomatization process and provided an essential reference for developing new functionalized extraction solvents.

Process for Producing High-Value Aromatics from Light Cycle Oil Using a Solvent Extraction Method

Process for Producing High-Value Aromatics from Light Cycle Oil Using a Solvent Extraction Method

Research on Product Yield Prediction and Benefit of Tuning Diesel Hydrogenation Conversion Device Based on Data-Driven System

In the refining process, a large amount of data are generated in daily production, and how to make full use of these data to improve the accuracy of simulation is the key to improving the operation level of refineries. At the same time, with the increasing environmental regulations and the improvement of gasoline and diesel quality standards, the ratio of diesel to gasoline is also changing with people’s demand for fuel consumption. Catalytic cracking light cycle oil (LCO) hydrogenation conversion technology (react LCO into gasoline, RLG) can produce modified diesel with high-octane gasoline, a high cetane number, and a low sulfur content, which improves the added value of the product. In this article, based on the production and operation data of a 1 million tons/year RLG device, a device yield prediction model was established using a deep neural network (DNN) algorithm, and the model was further optimized using a genetic algorithm (GA) to maximize the economic benefits of the device. As a result, the gasoline production yield increased by more than 3%. The experimental results show that the established model has a good reference value for improving the economic benefits of the RLG device.

Hydrocracking of hydrotreated light cycle oil for optimizing BTEX production: a simple kinetic model

Abstract The effect of the experimental conditions on the hydrocracking (HCK) of a hydrotreated light cycle oil (HDT LCO) was studied in this work. The catalyst tested was a 50/50 weight mixture of nickel-molybdenum-phosphorous on alumina (NiMo/Al2O3) and a commercial ZSM5 zeolite (HCK 50/50). The experimental conditions tested were 340, 350, 360, and 370 °C; 7.5 MPa; 0.9, 1.2, 1.5, and 1.8 h−1 LHSV, and H2/HC of 752 m3/m3. Two phases: gas and liquid, were obtained as HDK products. The gas phase consisted mostly of C1–C5 paraffins, iso-paraffins, and olefins. The liquid phase was characterized by GC-PIONA and was distributed in lumps as follows: NAPA by C11 to C13-naphthalenes; TET by C11 to C13-tetralins; IND by C9 to C13-indanes and indenes; AKB by C9 to C13-alkylbenzenes; BTEX by benzene, toluene, ethylbenzene, and xylenes; NAPE by C9 to C13-naphthenes; and PIP by C3 to C14 paraffin, iso-paraffin, and olefin type hydrocarbons. Using this classification, the results showed that increments in temperature and decrements in LHSV produced increments in the formation of gases, PIP, BTEX, and NAPE. At the same conditions, AKB, TET, NAPA, and IND decreased sharply. TET and NAPA derivatives were no longer present at high temperatures (360–370 °C). It seemed to be a limit of the BTEX formation directly related to the TET and IND presence, and it did not seem to depend on the transalkylation process of AKB hydrocarbons. Instead, AKB hydrocarbons were directly correlated to NAPE hydrocarbon formation by hydrogenation. A kinetic model was prepared. The model presented correlation coefficients higher than 98 %. The kinetic model that was made predicted that neither increasing the temperature nor lowering the LHSV would improve the BTEX formation when departing from this feedstock.

Hydrogenation of Light Cycle Oil to Produce Components of Winter and Arctic Diesel Fuels

This study proposed and experimentally investigated a novel approach to hydrogenation of light cycle oil (LCO) into components of winter and arctic diesel fuels (DF) environmentally classified as K5 as per the Technical Regulation of the Customs Union (TR CU) 013/2011 “On the requirements for automotive and aviation gasoline, diesel and marine fuels, jet fuels, and heating oils”. The process design involves atmospheric distillation of LCO with EBP 300˚C followed by hydrotreating. Hydrogenates with low concentrations of total sulfur (10 mg/kg) and arenes (28.6–38.0 wt %) and adequate low-temperature properties (CFPP≤–43˚C) were produced. An assessment of the physicochemical properties of the hydrogenates against applicable regulations for DF properties suggested that these hydrogenates can be effectively used as components of winter and arctic fuels by blending them into hydroisomerization diesel fractions (HIDF) and winter diesel fuels (WDF). An analysis of the main quality characteristics confirmed the feasibility of blending the LCO-derived hydrogenates into winter and arctic diesel fuels. Using GC×GC/MS examination, correlations were found between the hydrogenation process conditions, the physicochemical properties of the hydrogenates, and their detailed hydrocarbon compositions.