High-quality Fuels Research Articles

New Insights for High-Throughput CO2 Hydrogenation to High-Quality Fuel.

In the case of CO2 thermal-catalytic hydrogenation, highly selective olefin generation and subsequent olefin secondary reactions to fuel hydrocarbons in an ultra-short residence time is a huge challenge, especially under industrially feasible conditions. Here, we report a pioneering synthetic process that achieves selective production of high-volume commercial gasoline with the assistance of fast response mechanism. In situ experiments and DFT calculations demonstrate that the designed NaFeGaZr presents exceptional carbiding prowess, and swiftly forms carbides even at extremely brief gas residence times, facilitating olefin production. The created successive hollow zeolite HZSM-5 further reinforces aromatization of olefin diffused from NaFeGaZr via optimized mass transfer in the hollow channel of zeolite. Benefiting from its rapid response mechanism within the multifunctional catalytic system, this catalyst effectively prevents the excessive hydrogenation of intermediates and controls the swift conversion of intermediates into aromatics, even in high-throughput settings. This enables a rapid one-step synthesis of high-quality gasoline-range hydrocarbons without any post-treatment, with high commercial product compatibility and space-time yield up to 0.9 kggasoline ⋅ kgcat -1 ⋅ h-1. These findings from the current work can provide a shed for the preparation of efficient catalysts and in-depth understanding of C1 catalysis in industrial level.

Study on biomass and polymer catalytic co-pyrolysis product characteristics using machine learning and shapley additive explanations (SHAP)

Biomass and polymer catalytic co-pyrolysis can convert waste into higher-quality fuels, thereby reducing the use of fossil fuels to some extent. However, this process is an extremely complex thermochemical conversion, influenced by numerous factors such as feedstock properties, operational variables, and catalyst. Currently, experimental methods require substantial time and resource investment. Machine learning (ML) can fit and match input and output features based on existing data, achieving extremely high accuracy in the co-pyrolysis process. This study applies advanced ML models to study the biomass and polymer catalytic co-pyrolysis process, with a focus on the yield of pyrolysis products and the variations of the oxygen-containing components in the pyrolysis oil. The best-performing model is used for feature analysis of the correlation between inputs and outputs, based on game theory SHAP analysis. The results indicate a significant negative correlation between the polymer addition ratio and the generation of oxygen-containing components during the co-pyrolysis process. The addition of catalysts promotes the generation of pyrolysis gas during co-pyrolysis but suppresses the yield of pyrolysis oil. Additionally, catalysts significantly inhibit the formation of oxygenates in the pyrolysis oil. The XGBR model shows the highest performance in predicting pyrolysis oil yield, achieving R2 values of 0.98 during training phase and 0.91 during testing phase. The GBR model performs well in predicting the oxygenate composition of pyrolysis oil from small datasets.

Bioenergy potential from Ecuadorian lignocellulosic biomass: Physicochemical characterization, thermal analysis and pyrolysis kinetics

Lignocellulosic biomass offers a sustainable and renewable method for producing high-quality fuels and value-added chemicals. In this study, residues from peach palm (top, inner sheath, and meristem), sugarcane (top), and pineapple (mother plant) were characterized based on their physicochemical properties and thermal degradation behavior to estimate their bioenergy potential. The biomass residue kinetic constraints were analyzed using three isoconversional models: the Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), and differential Friedman (DF) models. Physicochemical characterization showed the peach palm top's notably high cellulose content of 35.71 ± 0.47 % wt. Calorific values of the residues ranged from 13.73 ± 0.08 to 16.91 ± 0.90 MJ kg−1. X-ray diffraction analysis indicated the carbonaceous and crystalline nature of the biomass residues. Mean activation energy values ranged from 105.02 to 370.10 kJ mol−1 for KAS, 111.50–360.99 kJ mol−1 for FWO, and 108.60–360.27 kJ mol−1 for DF. Finally, thermodynamic analysis revealed the endothermic nature of the pyrolysis process across the entire conversion range for the samples. Overall, these samples demonstrate major potential as feedstock for biorefineries and the development of Ecuador's circular economy.

Effect of Separating Air into Primary and Secondary in an Integrated Burner Housing on Biomass Combustion

Pellet burners, although they are commonly used devices, require high-quality fuels and yet are characterized by relatively high levels of CO and NO emissions and their variability. This article presents a combustion study of an original biomass burner that separates air into primary for biomass gasification and secondary for oxidizing the gasification products, with ducts placed in the housing of the burner. This study introduces a new burner design that separates air into primary and secondary streams within an integrated burner housing, aiming to optimize biomass combustion efficiency and reduce harmful emissions. Two burner designs were proposed, with a high secondary air nozzle (HCrown) and a low secondary air nozzle (LCrown). These two burners were compared with a typical retort burner (Ret). The LCrown burner reduced particulate matter emissions by 36% and CO emissions by 74% with respect to a typical retort burner. This study showed that the distance of the secondary air nozzles from the gasifying part has a significant impact on the operation of the burner and the possibility of reducing emissions of CO and NO. These results highlight the potential of the innovation to significantly improve combustion quality while simultaneously reducing environmental impact.

Catalytic solvothermal liquefaction of kitchen waste over iron-based catalysts addition and two-step method to produce high-quality fuels

The disposal of kitchen waste (KW) is a wide concern because of its high moisture content, foul odor, and low energy density. Solvothermal liquefaction (STL) can directly convert KW to bio-oil without pre-drying. This study investigated the effect of iron-based catalysts (Fe, Fe2O3, and Fe3O4) and a catalytic two-step method on bio-oil production, heteroatom distributions (N and S), and pollutant decompositions during STL of KW. From the comparison of three iron-based catalysts, the catalysis of metallic Fe significantly enhanced the bio-oil yield and quality, resulting in the highest yield (52.30 %) and a high heating value (35.86 MJ/kg) of bio-oil. Meanwhile, metallic Fe noticeably increased the fraction of lighter molecules in bio-oil to 71.30 %. During the catalytic two-step method process, the nitrogen and sulfur in the raw material were primarily transferred to the aqueous phase in the form of NH4+ and SO42-. The introduction of iron-based catalysts significantly promoted the esterification and reduction reactions. The bio-oil exhibited the highest ester content (77.96 %) when Fe3O4 was present while adding metallic Fe catalyst resulted in the highest hydrocarbon content of 28.16 %. Finally, a potential reaction pathway and mechanism of the catalytic STL of KW were proposed and discussed comprehensively. This study validates the use of iron-based catalysts and a two-step method to improve the yield and quality of bio-oil. This method reduces heteroatom content through associated hydrogenation and reduction reactions, demonstrating its potential for upgrading bio-oil into high-quality fuel.

Catalytic pyrolysis of corncob residues and pubescens over pristine and alkalis-treated HZSM-5

The catalytic pyrolysis of corncob residues and pubescens was carried out using HZSM-5 and alkalis-treated HZSM-5 as catalysts. HZSM-5 treated with different alkalis (TPAOH and a mixture of NaOH and Na2CO3) to get TPHZSM-5 and DHZSM-5. It was shown that the acid sites of the DHZSM-5 and TPHZSM-5 catalyst decreased compared to pristine HZSM-5. The hierarchical structures combining micro- and meso- porosity was formed in DHZSM-5, which was more conducive to promoting the formation of mono-phenols. However, the pore size of the catalyst decreased and the strength strong acid site increased with TPAOH treatment, which was beneficial for promoting C-O bond cleavage and generating more monocyclic aromatic hydrocarbons (MAHs). Under the same conditions, HZSM-5 was most beneficial for improving the yield of bio-oil (45.9 wt% of corncob residues and 52.0 wt% of pubescens). Analysis of the bio-oil showed that the catalytic pyrolysis of biomass over HZSM-5 achieved the highest PAHs yield (31.45 % from corncob residues and 18.38 % from pubescens), while TPHZSM-5 obtained the highest MAHs yield (5.92 % from corncob residues and 2.03 % from pubescens). However, DHZSM-5 catalyst appeared to have no significant effect on the increase of MAHs and PAHs yield, which may be attributed to its promotion of secondary polymerization of pyrolysis products. Additionally, the catalyst promoted the secondary cracking of pyrolysis vapor and reduced the average molecular weight (Mn) of the bio-oil. DHZSM-5 and TPHZSM-5 catalysts offered significant potential for the valorization of lignin, facilitating the production of value-added mono-phenolic compounds, MAHs, and high-quality fuels.

Developing Polymeric Carbon Nitrides for Photocatalytic H2O2 Production.

Hydrogen peroxide (H2O2) plays a crucial role in various applications, such as green oxidation processes and the production of high-quality fuels. Currently, H2O2 is primarily manufactured using the indirect anthraquinone method, known for its significant energy consumption and the generation of intensive by-products. Extensive research has been conducted on the photocatalytic production of H2O2via oxygen reduction reaction (ORR), with polymeric carbon nitride (PCN) emerging as a promising catalyst for this conversion. This review article is organized around two approaches. The first part main consists of the chemical optimization of the PCN structure, while the second focuses on the physical integration of PCN with other functional materials. The objective is to clarify the correlation between the physicochemical properties of PCN photocatalysts and their effectiveness in H2O2 production. Through a thorough review and analysis of the findings, this article seeks to stimulate new insights and achievements, not only in the domain of H2O2 production via ORR but also in other redox reactions.

CURRENT PROBLEMS IN THE COMBUSTIBLE MUNICIPAL WASTE MANAGEMENT – A CASE STUDY FOR PRE-RDF, RDF AND SRF MANAGEMENT IN POLAND

Refuse-derived fuel (RDF) is one of the municipal waste processing products generated inmechanical-biological installations. The RDF production allows energy recovery while reducingthe mass of landfilled waste. RDF is produced mainly from mixed waste stream with combustibleproperties. Currently, the main recipient of RDF fuels in Poland is the cement industry, whichaccepts only high-quality fuels. Annually a reduction of combustible waste share in the pre-RDFfraction intensifies difficulties in producing fuels with a sufficiently high calorific value. However,due to the energy transformation, it is planned that RDF would also be used in the heating sector.A positive aspect of this situation is the emergence of alternative recipients of RDF, even with theirlower calorific value. This may improve the market situation of RDF and reduce operation costs formunicipal installations in the long-term perspective.

Efficient hydrodeoxygenation of methyl palmitate over NiMo/ZrO2 catalyst with electron transfer between Ni and Mo

The hydrodeoxygenation of biomass into high quality fuels is one of the effective technologies to produce green diesel and solve the environmental pollution of fossil fuels at source. In this work, the catalytic performances of NixMoy/ZrO2 catalysts for methyl palmitate hydrodeoxygenation were evaluated, and the characterization results were combined to understand their role of physicochemical and structural properties in modulating the specific selectivity of alkanes. Under mild reaction condition (270 °C, 3 MPa), the Ni1Mo1/ZrO2 catalyst showed the best hydrodeoxygenation reactivity (conversion: 99.4%) and alkane selectivity (95.0%, hexadecane: 73.6%) of methyl palmitate. It was found that the electron transfer from Mo to Ni in Ni1Mo1/ZrO2 catalyst promoted the active site Ni anchoring and H2 molecules activation, which were associated with the better hydrodeoxygenation activity. In addition, the highest oxygen vacancies and Mo5+ content in Ni1Mo1/ZrO2 catalyst benefited the adsorption and breaking capacity of CO/C-O bonds and hexadecane yield. The Ni1Mo1/ZrO2 catalyst maintained excellent catalytic performance and structural stability after a long-term test of 60 h, which could be efficiently applied for hydrodeoxygenation of methyl palmitate.

An Optimized Method for Evaluating the Preparation of High-Quality Fuel from Various Types of Biomass through Torrefaction.

The pretreatment for torrefaction impacts the performance of biomass fuels and operational costs. Given their diversity, it is crucial to determine the optimal torrefaction conditions for different types of biomass. In this study, three typical solid biofuels, corn stover (CS), agaric fungus bran (AFB), and spent coffee grounds (SCGs), were prepared using fluidized bed torrefaction. The thermal stability of different fuels was extensively discussed and a novel comprehensive fuel index, "displacement level", was analyzed. The functional groups, pore structures, and microstructural differences between the three raw materials and the optimally torrefied biochar were thoroughly characterized. Finally, the biomass fuel consumption for household heating and water supply was calculated. The results showed that the optimal torrefaction temperatures for CS, AFB, and SCGs were 240, 280, and 280 °C, respectively, with comprehensive quality rankings of the optimal torrefied biochar of AFB (260) > SCG (252) > CS (248). Additionally, the economic costs of the optimally torrefied biochar were reduced by 7.03-19.32%. The results indicated that the displacement level is an index universally applicable to the preparation of solid fuels through biomass torrefaction. AFB is the most suitable solid fuel to be upgraded through torrefaction and has the potential to replace coal.

Ni modulates the coordination environment of cations in Fe3O4 to efficiently catalyze lignin depolymerization

Lignin shows great potential for sustainable production of high-quality fuels and value-added chemicals. The development of efficient and highly stable multifunctional catalysts for the depolymerization of lignin into aromatic chemicals remains a great challenge. In this work, environmentally friendly NiFe2O4 spinel catalyst characterizing with rich oxygen vacancies and porous structures was constructed by introducing Ni to modulate the coordination environment of cations in Fe3O4. Under optimal conditions, the conversion of alkali lignin catalyzed by NiFe2O4 reached 91.0%, the yield of liquid product reached 83.6% and the yield of aromatic monomer products was 31.7%. Combined results from catalyst characterization, product analysis and density functional theory calculations showed that the Lewis acidic center of the catalyst was significantly improved by the introduction of Ni, which promoted the C-O bond breaking in lignin. The Ni-O-Fe structure facilitated the adsorption of lignin substrates and reaction intermediates, which resulted in the improved depolymerization efficiency of lignin. The present work provides valuable insights into the depolymerization of lignin by spinel catalysts, and offers ideas for the future design and development of binary or even ternary spinel catalysts for the depolymerization of lignin.

Quantitative Estimation and Comparative Assessment of Particle Morphological Features and Energy Requirement During Hammer Milling of Softwood Chips and Wheat Straw

Highlights Quantified particle size and shapes generated during hammer milling of softwood and wheat straw. Size reductions in length and width correlated with milling energy requirement. Assessed the validity of existing comminution laws for predicting milling energy requirement. Improved milling energy requirement prediction for softwood based on size reductions. Abstract. The valorization of agricultural and woody residues into higher quality fuels is an attractive pathway and can contribute to decarbonizing the energy system. One essential step for the conversion of these residues to fuels is comminution through commercial mills. This study aimed to investigate the effects of feedstock, input feed size, and milling screen size on particle size and shape, as well as to validate the reliability of existing comminution laws for predicting energy requirements during hammer milling of agricultural and wood biomass. Additionally, the study proposed a new empirical correlation for comminution energy prediction, taking two-dimensional size reduction descriptors into consideration. A machine vision-based image processing method was used to estimate particle size, particle size distribution (PSD), and particle shape factors. The aspect ratio of wheat straw particles was 1.3 to 1.5 times larger than softwood particles, suggesting they are more fibrous. The shapes generated during hammer milling were estimated, with rectangular shapes being predominant. The specific energy requirement (SER) estimated for the hammer milling of softwood chips and wheat straw at different mill screen sizes (4, 8, and 12 mm) was found to be in the range of 153.2–25.5 kJ kg-1 and 38.5–16.1 kJ kg-1, respectively. The validity of existing comminution laws to predict the SER during hammer milling of softwood and wheat straw was tested at a fixed feed rate of 45 kg hr-1, and an improvement in SER prediction for softwood was achieved by formulating a new empirical correlation factoring size reductions in length and width. Further, the correlation developed for the SER for wheat straw was found to lack statistical significance. The findings of this study can be applied to improve the effectiveness of the comminution process, a critical precursor to numerous thermochemical conversion methods used for transforming biomass residues into valuable fuels. Keywords: Bioenergy, Biomass comminution, Machine-vision image analysis, Particle shape, Particle size distribution, Specific energy consumption.

Transitioning from hydrogen to methane in biorefineries: A sustainable route to clean energy and chemicals

This review discusses the sustainable transformation of low-quality hydrocarbon fuels, such as biomass-derived bio-oil, into valuable chemicals and clean fuels by introducing the concept of "methanotreating" that uses methane as a hydrogen source for the deoxygenation of bio-oils, thereby addressing environmental concerns associated with conventional hydrogen production. We explore the challenges of methane activation and its potential in biomass upgrading, highlighting the importance of catalyst selection and composition. Methanotreating is a promising and sustainable method for producing high-quality fuels and chemicals, with a deoxygenation performance of over 95%. This present work calls for further research and development in catalyst design and application to advance this innovative approach toward a greener and more efficient energy future.

Role of ZrO2 crystal on the hydrodeoxygenation of methyl palmitate over NiMo/ZrO2 catalyst

The hydrodeoxygenation of biomass into high-quality fuels is an effective strategy for solving the shortage of traditional fossil energy sources. In this paper, four NiMo/ZrO2 catalysts with different crystalline ZrO2 supports were synthesized and their catalytic properties for the hydrodeoxygenation of methyl palmitate were further investigated. Different crystalline ZrO2 exhibited different concentrations of oxygen vacancies, which could modulate the Ni valence state of NiMo/ZrO2 catalyst and affect adsorption and activation of CO bands, thus affecting catalyst activity and selectivity. Pure phase ZrO2, especially monoclinic ZrO2, was found to possess a stronger electron transfer capacity, a higher amount of Ni0 and oxygen vacancies on the surface than mixed phase ZrO2, which was conducive to dissociate H2 molecules and activate the CO bond. Thus, NiMo/m-ZrO2 (monoclinic phase) exhibited the highest hydrogenation conversion (99.5%) and liquid alkanes selectivity (96.7%, hexadecane: 68.8%) under relatively mild condition (240 °C, 3 MPa H2). In addition, the NiMo/m-ZrO2 catalyst maintained excellent catalytic stability without significant deactivation after continuous reaction for 86 h.

Petroleum-like fuels with substantially enriched branched iso-paraffins and benzenes via boehmite-assisted pyrolysis of oil shale

Oil shale (OS) is a potential alternative to substitute/supplement traditional fossil fuels, where catalyst-assisted OS pyrolysis has become a subject of general concern. While great progresses have been realized in this field, the pursuit of high-performance catalysts for a niche OS utilization still remains a formidable challenge, because most of the catalysts face various problems, including, high cost, unsatisfactory performances, etc. Based on a two-stage flash pyrolysis, we herein report our efforts about this issue by using boehmite, a low-cost industrially relevant material of an easy availability, as catalyst. We show that boehmite could arouse 17.0 % decreases in activation energy of OS pyrolysis. When the pyrolysis is executed at the 1st stage (450 °C), the content of hydrocarbons and short-chain aliphatic hydrocarbons (≤C13), which are desired for petroleum-like fuels (PLFs), increases evidently by 56.73 % and 158.5 %, respectively, while that of heteroatomic compounds and long-chain aliphatic hydrocarbons (≥C20), which are undesired for PLFs, decreases distinctly by 60.09 % and 41.6 %, respectively, indicating an evident improvement in the quality of the pyrolysates. Fascinatingly, the content of branched iso-paraffins, especially, monomethyl-, dimethyl- and trimethyl-branched paraffins, which are either efficient octane number boosters, important tectons for functional surfactants, or significant component for high-quality fuels of excellent low-temperature performances, increases substantially by ca. 180.2 % from ca. 16.02 % to 44.89 %. For the 2nd stage at 585 °C, besides a distinctly improved quality of the pyrolysates, the content of benzene, toluene, xylene and trimethylbenzene, which are value-added chemicals broadly employed in numerous industrial fields of paramount importance, is enriched distinctly by 94 %, 65.2 %, 13 %, and 19 %, respectively. We find that the concentration of the Brönsted acid sites (BASs) of the employed boehmite, which contain 94 % medium and strong BASs, is substantially lower than that of Lewis acid sites (LASs), which contain merely 54.91 % medium and strong LASs, such that the competitive-collaborative actions of BASs and LASs confer boehmite with outstanding catalytic reactivity.

Co-pyrolysis of biomass with Red Mud: An efficient approach to improving bio-oil quality and resourceful utilization of the iron in Red Mud

Co-pyrolysis of biomass with Red Mud was used to boost up the quality of the produced bio-oil and recover iron from Red Mud. The influences of five different biomass species and impregnation pretreatment were investigated. It was found that co-pyrolysis could significantly improve the bio-oil quality, decreasing the acidity from 173.28 to 1.18 mg KOH/g due to the decarboxylation of carboxylic acids into ketones under the catalysis of Red Mud and boosting up the HHV from 20.05 to 31.80 MJ/kg with an energy efficiency of 72.56%. Meanwhile, the soluble alkalinity of Red Mud declined from 65.34 to 5.26 mg HCl/g, which is very crucial to mitigate the harmfulness and perniciousness to the environment. The characterizations of XRD, 57Fe Mössbauer spectroscopy and XPS confirmed that the weak magnetic Fe2O3 and FeOOH in Red Mud could be completely transformed into stronger magnetic Fe3O4. For this reason, the magnetic separation iron recovery reached up to 92.25% with iron grade of 66.12%. The findings in the research not only open the avenue for efficient biomass conversion to high quality fuels, but also provide an efficient approach to resourceful utilization of Red Mud.

Аналіз та оцінювання тенденцій формування індикаторів стану електроенергетичного ринку України як основного базису для формування її електроенергетичної безпеки

Assessment of the current state of electricity security in Ukraine and trends in its functioning is an urgent and essential task for the national economy and security. The electricity sector is the primary sector of Ukraine's economy, which produces electricity from various sources: coal, fuel oil, natural gas, nuclear energy, hydropower, renewable energy sources, etc. However, Ukraine faces several problems in the electricity sector, such as low energy efficiency, high dependence on imported fuel and energy resources, outdated infrastructure, insufficient integration with the European energy space, etc. This threatens Ukraine's energy security and requires developing and implementing effective strategies and mechanisms to ensure it. It is necessary to use a comprehensive approach based on a systematic analysis of the internal and external environment of the electricity sector to assess the current state of Ukraine's electricity security and trends in its functioning, identifi-cation of critical factors and indicators that characterize its shape and dynamics, as well as the use of scientifically based methods and models for their quantitative and qualitative assessment. This approach will not only provide an objective assessment of the current state of Ukraine's electricity security but also identify strengths and weaknesses, opportunities, and threats to its further development and for mulate proposals for priority areas and mechanisms to improve Ukraine's electricity security in the future. The energy sector is the basis for developing national economies and is vital in ensuring their competitiveness and economic growth. From the standpoint of sustainable development of the national economy, energy security, its forms, and level are of utmost importance for society, present and future generations, and the prospects for further joint work of the world's countries in addressing global challenges of sustainability and security of human existence. For the national economy of Ukraine, energy security today forms the prerequisite for the country's recovery from the conse-quences of military operations, increasing the lost economic growth rates and protecting the country and its population from any energy shortage. Energy security is manifested in the confidence that affordable and high-quality fuels will remain necessary and available under both routine and emergency conditions of economic activity. Keywords: assessment of the electricity market, electricity supply, electricity market, electricity security, trends in the functioning of electricity security.

Machine learning modeling for optimization of sulfur compounds separation from fuels: Process optimization for reduction of environmental pollution

Development of theoretical models for reduction of sulfur emission and also the material consumption is of great importance for petroleum refinery to obtain high-quality fuels. The latter can be done by employing advanced optimization techniques. In this study, we have developed a modeling methodology for optimization of petroleum refinery in fuel production. Some measured data have been collected for the modeling and computational optimization. Each data point is comprised of four input characteristics: reactor pressure (bar), reactor temperature (°C), initial sulfur concentration (ppm), and dose (g). Outputs for the modeling include sulfur concentration (ppm), emission (%), and HDS cost ($). For modeling, the Adaboost ensemble model is applied on top of the three fundamental models Linear Regression, Gaussian Process Regression, and Bayesian Ridge. On the available dataset, the models are tweaked using the grasshopper optimization algorithm (GOA) method, and then the optimal combination of models and parameters is selected for each output. For sulfur content and emission characteristics, the ADA-GPR model is the most accurate; however, the ADA-BRR algorithm performs the best for calculating the HDS cost. Using these models, the R2-score for outputs is 0.970, 0.950, and 0.999, respectively for sulfur concentration, emission percentage of SO2, and HDS cost.

Reduction of fossil CO2 emissions of engine fuels by integration of stabilized bio-oil distillation residue to a crude-oil refinery hydrocracking process

Utilization of waste lignocellulosic biomass to produce high-quality fuels with renewable carbon content using existing refinery infrastructure is an important step towards carbon neutrality. Direct hydroprocessing of pyrolysis bio-oil to liquid biofuels is technically challenging due to its wide fractional and complex chemical composition that requires harsh reaction conditions associated with extensive biocarbon loss to the gaseous products. We have proposed a novel bio-oil hydroprocessing strategy based on 1) bio-oil hydrotreatment (stabilization), 2) fractionation of the stabilized bio-oil and 3) co-processing of the fractions in appropriate refinery processes. In this work, we focus on the co-processing of the stabilized bio-oil distillation residue (SBDR, b.p. 360+°C) with vacuum gas-oil (VGO) in a hydrocracking fixed bed reactor under conventional conditions. This allowed us to maximize biogenic carbon content (92%) in the liquid transportation fuels as confirmed by the distribution of 14C (obtained by Accelerator Mass Spectrometry) into the corresponding fractions. i.e. gases, naphtha, kerosene, diesel and distillation residue. Reduction of the fossil CO2 emission was 3 times higher for the naphtha fraction compared with E10 gasoline; 2.4 times higher for the diesel fraction compared with B7 diesel (7 vol% FAME). Detailed analysis of the products via GC × GC-TOFMS, 13C NMR, and FTIR together with the standardized methods demonstrated that fuel distillates met requirements for conventional fuels with only negligible effect of the SBDR on physicochemical properties of products and catalyst stability. This shows that the co-hydrocracking of SBDR is a suitable process to maximize liquid fuel production with increased biogenic carbon content.

Rhodium-Based Catalysts: An Impact of the Support Nature on the Catalytic Cyclohexane Ring Opening

Because of the growing demand for high-quality fuels, the light cycle oil fraction improvement including cetane number improvement is important. The main way to reach this improvement is the ring opening of cyclic hydrocarbons, and a highly effective catalyst should be found. Cyclohexane ring openings are a possible option to investigate the catalyst activity. In this work, we investigated rhodium-loaded catalysts prepared using the commercially available industrial supports: single-component ones, SiO2 and Al2O3; and mixed oxides CaO + MgO + Al2O3 and Na2O + SiO2 + Al2O3. The catalysts were prepared by incipient wetness impregnation and investigated by N2 low-temperature adsorption-desorption, XRD, XPS, DRS UV-Vis and DRIFT spectroscopy, SEM, and TEM with EDX. The catalytic tests were performed in cyclohexane ring opening in the range of 275-325 °C. The best result was demonstrated by the sample 1Rh/CaMgAlO: the selectivity to n-hexane was about 75% while the cyclohexane conversion was about 25% at 275 °C. The space-time yield was up to 12 mmoln-hexane gcat-1h-1.