Diesel Components Research Articles

High-efficiency treatment of oily wastewater by photocatalytic in-situ Fenton oxidation under visible light

Oily wastewater poses a significant threat to environmental safety, and complex water environments have caused numerous disturbances in oil pollution treatment. Therefore, constructing composite systems is expected to improve oil pollution treatment efficiency. This study developed an efficient photocatalytic in-situ Fenton oxidation system, HTCC@ZnFe2O4/Ag3PO4 (HZFA), loaded onto polypropylene spheres (PP) for treating oily wastewater (diesel oil) in complex environments. The built-in electric field of HZFA promotes photogenerated carrier separation, enhancing photocatalytic effect. At a diesel concentration of 3.2 g/L, performance of HZFA degraded diesel in deionized water and artificial seawater (ASW) were 60.80 % and 52.62 %, respectively, much higher than a pure photocatalytic system (13.84 %). The dual system compensated for single system defects like instability and narrow application range, achieving 8 effective cycles in ASW. Experimental and computational results showed that high oxidation and reduction potentials in the dual system promoted hydrocarbon oxidative degradation and H2O2 production/activation. The amount of OH, O2−, and h+ produced in different environments is fundamental for the stabilization of catalytic degradation by HZFA. GC–MS and DFT analysis revealed potential oxidative chain-breaking processes for diesel components like alkanes, aromatics, alcohols, acids, aldehydes, and esters. This study offers a new method for green and efficient oily wastewater treatment, overcoming inherent defects of traditional Fenton, with broad application prospects.

Effects of mono- and multicomponent nonaqueous-phase liquid on the migration and retention of pollutant-degrading bacteria in porous media

The successful implementation of in-situ bioremediation of nonaqueous-phase liquid (NAPL) contamination in soil-groundwater systems is greatly influenced by the migration performance of NAPL-degrading bacteria. However, the impact and mechanisms of NAPL on the migration/retention of pollutant-degrading bacteria remain unclear. This study investigated the migration/retention performance of A. lwoffii U1091, a strain capable of degrading diesel while producing surfactants, in porous media without and with the presence of mono- and multicomponent NAPL (n-dodecane and diesel) under environmentally relevant conditions. The results showed that under all examined conditions (5 and 50 mM NaCl solution at flow rates of 4 and 8 m/d), the presence of n-dodecane/diesel in porous media could reduce the migration and enhance retention of A. lwoffii in quartz sand columns. Moreover, comparing with mutlicomponent NAPLs of n-dodecane, the monocomponent NAPLs (diesel) exhibited a greater reduction effect on the retention of A. lwoffii in porous media. Through systemically investigating the potential mechanisms via tracer experiment, visible chamber experiment, and theoretical calculation, we found that the reduction in porosity, repulsive forces and movement speeds, the presence of stagnant flow zones in porous media, particularly the biosurfactants generated by A. lwoffii contributed to the enhanced retention of bacteria in NAPL-contaminated porous media. Moreover, owing to presence of the greater amount of hydrophilic components in diesel than in n-dodecane, the available binding sites for the adsorption of bacteria were lower in diesel, resulting in the slightly decreased retention of A. lwoffii in porous media containing diesel than n-dodecane. This study demonstrated that comparing with porous media without NAPL contamination, the retention of strain capable of degrading NAPL in porous media with NAPL contamination was enhanced, beneficial for the subsequent biodegradation of NAPL.

Proposal automatic water purging system for machinery in high humidity environments controlled by an ECU

This paper presents an advanced automatic water discharge system tailored for diesel-powered machinery, particularly for vehicles operating in diverse climates, including humid coastal regions. The system is designed to protect fuel circuits in tanks and diesel engines of boats, offering either automatic or semi-automatic protection against oxidation and corrosion. This enhancement extends the lifespan of diesel components and pipelines while simultaneously reducing maintenance costs and intervention times. Additionally, the system improves fuel purity, resulting in increased engine power and efficiency. The proposed solution was experimentally validated using an Arduino board coupled with a water-sensitive detector in diesel fuel, suitable for installation in diesel filters or tanks. Experimental findings demonstrated a remarkably swift separation time of 150 microseconds for diesel and water at a pressure of 1 bar, achieving an impressive efficiency of 99.84%. The system's rapid and effective separation capability highlights its practical value, particularly in scenarios where efficient water removal is critical to sustaining engine performance and longevity.

Catalytic Valorization of Organic Solid Waste: A Pilot-Scale Run of Sugarcane Bagasse

Organic solid waste treatment is crucial for enhancing environmental sustainability, promoting economic growth, and improving public health. Following our previous organic solid waste upgrading technique, a further two-step pilot-scale run, using sugarcane bagasse as the feedstock, has been successfully conducted with long-term stability. Firstly, the sugarcane bagasse was treated under mild conditions (400 °C and 1 bar of CH4), and this catalytic Methanolysis treatment resulted in a bio-oil with a yield of 60.5 wt.%. Following that, it was subjected to a catalytic Methano-Refining process (400 °C and 50 bar of CH4) to achieve high-quality renewable fuel with a liquid yield of 95.0 wt.%. Additionally, this renewable fuel can be regarded as an ideal diesel component with a high cetane number, high heating values, a low freezing point, low density and viscosity, and low oxygen, nitrogen, and sulfur contents. The successful pilot-scale catalytic upgrading of sugarcane bagasse further verified the effectiveness of this methane-assisted organic solid waste upgrading technique and confirmed the high flexibility of this innovative technology for processing a wide spectrum of agricultural and forestry residues. This study will shed light on the further valorization of organic solid waste and other carbonaceous materials.

Remote island renewable transition potential: Affordable, reliable and sustainable generation optimisation for Mornington island

Remote islands, comprising over one-sixth of the Earth's surface area and home to approximately 9% of the global population, face formidable challenges in securing affordable, sustainable, and reliable energy. This paper presents a pioneering investigation into Mornington Island's transition from diesel reliance to renewable energy predominance over the next four decades. By demonstrating the tangible benefits of renewable energy implementation on Mornington Island, this research provides compelling simulated evidence that blending traditional and renewable energy sources can revolutionize energy provision for small island communities. Employing hybrid Wind-Solar renewable energy systems bolstered by an effective battery storage system (ESS), this innovative approach ensures a seamless shift to renewable energy, resilient against seasonal variations and extreme weather events such as cyclones. Our analysis, conducted through a tech-economic model simulating each 5% increment of renewable energy penetration, reveals that renewable energy outperforms traditional diesel generation in terms of affordability over a 40-year operational span. Specifically, a 95% renewable energy penetration yields the lowest levelized energy cost ($162.2/MWh), resulting in a remarkable $8.54 million reduction in diesel costs. A 5% diesel component secures annual energy supply, bridging the gap during periods of seasonal renewable energy variability and extreme cyclonic weather. While achieving 100% renewable energy generation is financially feasible, challenges arise in scaling battery capacity to stabilize energy supply during cyclone seasons. Moreover, our carbon accounting model indicates that although the construction of renewable energy infrastructure entails some indirect (Scope 3) carbon emissions, a 95% renewable penetration mitigates emissions by 90% compared to traditional diesel generation, amounting to a reduction of 39.17 kilotons over the 40-year period. This comprehensive study provides policymakers with invaluable insights, fostering a holistic understanding of the financial, technical, environmental, and political dimensions inherent in island energy transitions.

Numerical simulation of diesel particulate filter flow characteristics optimization: From the perspective of pore structure parameters and inlet velocity

The diesel particulate filter (DPF) with porous media structure has become an essential component for diesel engines to satisfy increasingly strict emission standards. This study constructed a porous media structure model of DPF, and optimized its boundary to conduct a simulation on the flow characteristic with different influencing parameters using the lattice Boltzmann method (LBM). Results showed that the increase of the average flow velocity of the DPF model reduced the pressure drop, indicating that the flow probability of model improved. In addition, the porosity application range was expanded. The visualization and quantization of the velocity and pressure distribution with the DPF revealed that an increase of the wall thickness resulted in a higher pressure drop of the DPF, but a lower flow velocity. Further, the fractal dimension of the porous media exhibited no direct relationship with the DPF pressure and velocity performance; however, the outlet velocity and pressure drop of the model were optimized within the different porosity. Moreover, both the increase in the spectral dimension and model optimization improved the DPF permeability. The impact of increasing the inlet velocity on the pressure drop was particularly significant as it accelerated the rate of pressure drop, illustrating that a smoother porous media boundary was conducive to improve the flow performance of DPF, which facilitated a better scheme for the design of DPF porous media.

Green synthesis of metal nanoparticles and application of nanoadditives in diesel fuel: bibliometric analysis

The problem of obtaining metal nanoparticles considering environmental risks in connection with the use of synthesis products in mixtures of new types of diesel fuel has been studied. An analysis of existing research on these topics was carried out. Based on the data sets obtained using the Dimensions and OpenAlex services, the characteristics of the studies were determined. To analyze the problem of green synthesis of nanoparticles, a dataset of 6,062 journal articles published from 2001 to October 2023 was used. The use of nanoparticles as diesel fuel components was investigated using a dataset of 540 journal articles published from 2005 to October 2023. The leading countries and organizations by the number of publications and citations have been identified. Based on the analysis of coauthorship, the issue of international cooperation is considered. The most significant publications were determined by the number of citations. Using methods of visual analysis of data on research keywords, their trends and prospects were determined. In addition, an assessment was made of the development of the problem of using “green” methods for obtaining nanoparticles used as components of diesel fuel.

Rapid Prediction of ANFO Based Explosives through ATR-FTIR Analysis – Use of ATR-FTIR in Explosives

Ammonium Nitrate Fuel Oil (ANFO) is preferred mining explosives in worldwide. It is composed of ammonium nitrate (94-96%) and liquid hydrocarbon as fuel oil (4-6%), which is detonated through an explosive charge. In India, Forensic Science Laboratories received many criminal cases from investigation agencies for chemical analysis of sample as semi-solid materials supposed to be explosive material. In the present study, we developed an Attenuated Total Reflectance - Fourier Transform Infrared Spectroscopy (ATR-FTIR) procedure for easily analyzing the real crime exhibits related to ANFO based explosives. Firstly, semi-solid material is directly used on the ATR. Further, the sample is extracted using appropriate solvents (diethyl-ether/acetone). Extracts are subsequently analyzed on ATR-FTIR in comparison with standards for ammonium nitrate and diesel. The residue after acetone extract is dried and left solid material directly used on ATR for the detection of water-soluble compounds. The results significantly showed the presence of ammonium nitrate with the residue of diesel in a real crime exhibit. Hence, the proposed modify procedure can be advantageous for the rapid detection of diesel components mixed in ammonium nitrate through ATR-FTIR spectroscopy without the use of other chemical or instrumental analysis in a short period of time and also for easily identifying the presence of organic explosives (if any) among different samples received for the forensic opinion.

Speed of sound measurements and derived thermodynamic properties of bio-jet fuel components at saturation: N-butylcyclohexane

The composition of bio-jet fuels, i.e., the total content of hydrocarbons such as n-alkanes, iso-alkanes, cycloalkanes and aromatics, reached 85 % to 95 %, are mainly defining the thermophysical properties of bio-jet fuels. Short-chain cycloalkanes, such as n-butylcyclohexane, are one of the main components of bio-jet fuel. N-butylcyclohexane is included as one of the components of diesel fuel surrogate mixture. Therefore, more information on n-butylcyclohexane thermophysical properties in surrogate mixtures is required. In the present work the speed of sound in n-butylcyclohexane at saturation in the temperature range from (276 to 456) K has been measured using the pulse method with a constant (acoustic) sounding base. The combined expanded absolute and relative uncertainties (0.95 level of confidence, k = 2) of the temperature and speed of sound measurements are estimated to be 20 mK and 0.2 %, respectively. The measured speed of sound data together with reported density data were used to calculate the derived thermodynamic properties (kS,kT, and CP/CV) of n-butylcyclohexane at saturation.

Spray ignition of n-alkanes in diesel and jet fuels: Effects of temperature, pressure, and N2 and NO addition

This study investigates the effects of NO-addition and N2-dilution on the autoignition process of n-C10–n-C14 alkanes, which are important components of diesel and kerosene-based jet fuels. The study is motivated by the need for a comprehensive understanding of the effects of nitrogen oxides (NOx) and N2 on the fuel ignition process. This understanding is essential to enable the effective employment of advanced combustion engine technologies, such as exhaust gas recirculation (EGR) and Rich-Quench-Lean (RQL) gas turbine combustors. Ignition delay time (IDT) measurements were performed under various combustion conditions relevant to practical engine operation and low-temperature oxidation chemistry in a constant-volume combustion spray chamber device. The experimental results show that N2-dilution consistently results in longer IDTs for the fuels tested. On the other hand, NO-addition has a temperature-dependent effect, shortening the IDTs for T > 692 K and vice versa. The magnitude of reactivity promotion or inhibition depends on NO concentration, temperature, pressure, and equivalence ratio. Based on the tested NO-addition levels, the inhibition of reactivity is approximately ten times greater than the promotion of reactivity caused by NO. The study fills a gap in the literature by providing comprehensive fundamental combustion data for n-C10–n-C14 fuels. This data, along with the corresponding analysis, can be used by engine researchers in developing more efficient and cleaner combustion engine technologies.

Monitoring of in-situ chemical oxidation for remediation of diesel-contaminated soil with electrical resistivity tomography

In-situ chemical oxidation (ISCO) with persulfate, an electrically conductive oxidant, provides a powerful signal for noninvasive geophysical techniques to characterize the remediation process of hydrocarbon contaminants. In this study, remediation with ISCO is conducted in laboratory sandboxes to evaluate the ability of electrical resistivity tomography (ERT) for monitoring the base-activated persulfate remediation process of diesel-contaminated soil. It was found that the resistivity of contaminated sand significantly decreased from 846 Ω·m to below 10 Ω·m after persulfate injection, and all measured chemical parameters showed a noticeable increase. Natural degradation and contamination plume migration were not evident in a reference sandbox without treatment. The area with a resistivity ratio < 0.95 based on imaging before and after injection indicated downward migration of the oxidation plume due to density-driven flow. A comparison between remediation and reference sandboxes showed that the observed resistivity decrease can be due to both contaminant degradation as well as the oxidation plume itself in the contaminated source zone. In contrast, the resistivity decrease in the area with low contamination concentration is attributed to the oxidation plume alone. The derived relationships between resistivity and contaminant indicators further emphasize that the contribution of contaminant consumption to resistivity change in the source area is 25.6%, while it is <16% in the low or non-contaminated area. Although this study showed that resistivity is not solely affected by the chemical transformation of diesel components, it can be combined with sampling data to allow an assessment of the effectiveness of ISCO treatment and to identify target areas for subsequent treatment.

Increasing in situ bioremediation effectiveness through field-scale application of molecular biological tools.

Leveraging the capabilities of microorganisms to reduce (degrade or transform) concentrations of pollutants in soil and groundwater can be a cost-effective, natural remedial approach to manage contaminated sites. Traditional design and implementation of bioremediation strategies consist of lab-scale biodegradation studies or collection of field-scale geochemical data to infer associated biological processes. While both lab-scale biodegradation studies and field-scale geochemical data are useful for remedial decision-making, additional insights can be gained through the application of Molecular Biological Tools (MBTs) to directly measure contaminant-degrading microorganisms and associated bioremediation processes. Field-scale application of a standardized framework pairing MBTs with traditional contaminant and geochemical analyses was successfully performed at two contaminated sites. At a site with trichloroethene (TCE) impacted groundwater, framework application informed design of an enhanced bioremediation approach. Baseline abundances of 16S rRNA genes for a genus of obligate organohalide-respiring bacteria (i.e., Dehalococcoides) were measured at low abundances (101-102 cells/mL) within the TCE source and plume areas. In combination with geochemical analyses, these data suggested that intrinsic biodegradation (i.e., reductive dechlorination) may be occurring, but activities were limited by electron donor availability. The framework was utilized to support development of a full-scale enhanced bioremediation design (i.e., electron donor addition) and to monitor remedial performance. Additionally, the framework was applied at a second site with residual petroleum hydrocarbon (PHC) impacted soils and groundwater. MBTs, specifically qPCR and 16S gene amplicon rRNA sequencing, were used to characterize intrinsic bioremediation mechanisms. Functional genes associated with anaerobic biodegradation of diesel components (e.g., naphthyl-2-methyl-succinate synthase, naphthalene carboxylase, alkylsuccinate synthase, and benzoyl coenzyme A reductase) were measured to be 2-3 orders of magnitude greater than unimpacted, background samples. Intrinsic bioremediation mechanisms were determined to be sufficient to achieve groundwater remediation objectives. Nonetheless, the framework was further utilized to assess that an enhanced bioremediation could be a successful remedial alternative or complement to source area treatment. While bioremediation of chlorinated solvents, PHCs, and other contaminants has been demonstrated to successfully reduce environmental risk and reach site goals, the application of field-scale MBT data in combination with contaminant and geochemical data analyses to design, implement, and monitor a site-specific bioremediation approach can result in more consistent remedy effectiveness.

Production of transportation fuels via hydrotreating of scrap tires pyrolysis oil

The hydrotreating of scrap tires pyrolysis oil over commercial Ni-Mo/Al2O3 catalyst was researched for the best processing scheme allowing the production of high-quality alternative transportation fuels components of gasoline, jet, diesel, and marine fuel. Despite the initial high content of olefins, aromatics, sulfur, and nitrogen in pyrolysis oil, fuel components obtained by redistillation after the hydrotreating at 360 °C and 10 MPa met the majority of standard fuel specifications. Although the octane number of the naphtha fraction was lower, this fraction can be used as acomponent of the gasoline pool directly or after the catalytic reforming. Kerosene fraction can be utilized as jet fuel after the additional mild hydrotreatment or blending with hydroprocessed esters and fatty acids (HEFA) to decrease aromatics content. Diesel fraction can be blended with hydrotreated vegetable oils (HVO) to fulfill the density and cetane index specification. The bottom residue can be utilized as a low-sulfur fuel oil component in marine transportation.

Catalytic hydroprocessing of camelina oil/AGO mixtures over NiMoP/γ-Al2O3 catalysts

Inedible camelina oil (CSO) contains fatty acids with a high degree of unsaturation (1.8 double bonds per fatty acid on average). CSO was hydrotreated at temperatures 340–370 °C, pressures of 15–50 bar, and liquid hour space velocities (LHSVs) of 0.8–1.1 h-1 for the production of hydrocarbons that are usable as diesel components. First, hydrotreating pure CSO at 340–370 oC and low hydrogen pressures of 15–25 bar led to the formation of a mixture of n-/iso- alkanes, aromatics, and higher olefins. The presence of CC double bonds in the CSO molecule affected the progress of the side reactions and caused rapid deactivation and coking of the catalyst, especially at low hydrogen partial pressure. Hydrotreatment co-processing of polyunsaturated CSO and partially hydrogenated CSO was then done with two different gas oils or two paraffinic solvents in the range of concentration 5–20%. Co-hydrotreatment took place in a bench-scale trickle-bed reactor using commercial NiMoP/γ-Al2O3 catalysts (catalysts A and B) and a prepared catalyst, NiMoCuP/ZrO2-γ-Al2O3 (catalyst C). High triacylglyceride conversion to hydrocarbons was achieved when CSO was hydrogenated in a mixture with paraffinic solvents on NiMoP/γ-Al2O3 catalysts at hydrogen partial pressures above 30 bar and temperatures above 350 oC. CSO decarboxylation/decarbonylation reactions prevailed over hydrodeoxygenation. Hydrodeoxygenation (72%) was predominant for catalyst C with significant methanation of CO and CO2. There was a complete TAG conversion into hydrocarbons when co-processing a mixture of CSO and atmospheric gas oil at a temperature of 360 oC, LHSV of 0.8 h-1, a hydrogen pressure of 50 bar, and various ratios of hydrogen to raw material from 312 to 656 NL.L-1. The deoxygenation activity decreased in the order of catalysts C>B>A. Increasing the ratio of H2 to feed had a positive effect on the composition and properties of the liquid product. During experiments with catalyst C at 50 bar, 370 °C, and ratios of hydrogen to raw material of 293–656 NL.L-1, the cetane index increased from 46 to 58, and the polyaromatic content decreased from 12.5 to 4.4 wt%. The sulphur and nitrogen contents of the product (29.5 mg.kg-1 and 13.2 mg.kg-1) were higher than expected. In the case of catalyst C, the degree of desulphurization was lower than that of catalysts A and B.

Integrated LC-MS/MS and transcriptome sequencing analysis to evaluate the feasibility of green and red prickly ash as biodiesel crops

Fatty acids are expected to replace fossil fuels for bioenergy and are also important raw materials in industrial production. Prickly ash fruits are rich in fatty acids and can be used as plant raw materials for industrial oil extraction and development. Here, we performed qualitative and quantitative analyses of fatty acids in green and red prickly ash fruits using transcriptome and LC–MS/MS. Myristic acid, vaccenic acid, linoleic acid, γ-linolenic acid, and α-linolenic acid were the main fatty acids detected. The carbon chain lengths of the main components of diesel are C15–C19, and the main components of prickly ash fruit oil are C16 and C18 fatty acids, which can be used to prepare biodiesel by acid-catalyzed esterification. In addition, the fatty acid biosynthetic pathway and RDA showed that KASII plays a key role in fatty acid synthesis.

Experimental and kinetic modeling study of α-methylnaphthalene laminar flame speeds

α-Methylnaphthalene (AMN) is the primary reference bicyclic aromatic compound of diesel, and it is commonly used as a component of diesel, kerosene and jet-fuel surrogates formulated to describe real fuel combustion kinetics. However, few experimental data on neat AMN combustion are available in the literature. This work provides the first measurements of laminar flame speed profiles of AMN/air mixtures at 1 bar varying the initial temperature from 425 to 484 K, and equivalence ratio (φ) between 0.8 and 1.35 paving the way for the kinetic study of AMN combustion chemistry at high temperatures (>1800 K). The experimental data obtained in a spherical reactor are compared with kinetic model simulations. Specifically, the AMN kinetics is implemented from its analogous monocyclic aromatic compound, i.e., toluene, through the analogy and rate rule approach. This method allows to develop kinetic mechanisms of large species from the kinetics of smaller ones characterized by analogous chemical features, namely the aromaticity and the methyl functionality in the case of toluene and AMN. In doing so, it is possible to overcome the need of high-level electronic structure calculations for the evaluation of rate constants, as their computational cost increases exponentially with the number of heavy atoms of the selected species. To assess the validity of this approach, ab initio calculations are performed to derive the rate constants of the H-atom abstraction reactions by H, OH and CH3 radicals from both toluene and AMN. The kinetic model obtained satisfactorily agrees with the measured laminar flame speed profiles. Sensitivity and flux analyses are performed to investigate similarities and differences between the main reaction channels of toluene and AMN combustion, with the former leading to ∼6 cm/s faster flame speed at almost identical conditions (P=1 bar, T∼425 K), as evidenced by both kinetic model simulations and experimental findings.

High-performance total sulfur removal from diesel fuel using amine functionalized biochar: Equilibrium, kinetic study and experimental design

The presence of sulfur components in diesel fuel can produce SOx gases, which emit from the combustion of diesel fuel and cause serious environmental problems. In this study, four various adsorbents biochar/CuFe2O4 (BC/CuFe2O4), oxidized biochar/CuFe2O4 (O-BC/CuFe2O4), ethylene diamine-functionalized biochar/CuFe2O4 (Et-BC/CuFe2O4) and melamine-functionalized biochar/CuFe2O4 (Me-BC/CuFe2O4) were prepared for application in the total sulfur (all sulfur compounds) adsorption from diesel fuel. The prepared samples were characterized by XRD, TGA, VSM, FT-IR, FE-SEM, TEM and Raman techniques. Also, the Response Surface Methodology-Box-Behnken design was used in order to optimize adsorption key parameters included contact time, amount of adsorbent and percentage of Cu. Because of the presence of CuFe2O4 nanoparticles, all of the prepared adsorbents can be regenerated and reused for consecutive adsorption tests. The π-complexation can be formed between Cu in adsorbents and aromatic sulfur compounds. Also Cu+2 can be a proper cation for adsorption of mercaptan components from diesel fuel. Formation of oxygenated group in O-BC sample and presence of –NH2 functions in Et-BC and Me-BC samples can form hydrogen bonding with sulfur atom in sulfur compounds and create a very high adsorption capacity. Kinetic as well as isotherm studies showed that total sulfur adsorption by the prepared adsorbents followed second order and Langmuir adsorption model. For the sample of Me-BC/CuFe2O4, the adsorption capacity was obtained 1666.7 mg/g, while this value was 192.3 mg/g in the presence of BC adsorbent. It was found that 98.6% of total sulfur was removed by Me-BC/CuFe2O4. Thermodynamic data demonstrated that total sulfur adsorption was spontaneous and followed an endothermic path. Regeneration of the prepared adsorbents employing NaOH solution showed that the adsorbents have suitable reusabilities after five sorption and desorption runs.

Synergy of blending hydrotreated and hydrocracked kerosene in the production of jet fuel

Aviation kerosene is the fastest growing transportation fuel. Regardless of the ambition to replace it by SAF, consumption of the mineral component in JET fuel will grow. In oil refineries, kerosene fractions are used to produce JET fuel and as a component of diesel fuel. These fractions can differ in origin and composition. In this article the possibility of blending hydrocracked kerosene used for JET production and hydrotreated kerosene used for diesel fuel production was investigated. It was concluded that significant synergies can be achieved by blending of these fractions in terms of increasing JET fuel production by up to 2.5 times, controlling the aromatics content of hydrocracked kerosene and obtaining a fraction for blending of diesel fuel with improved low temperature properties.

Variation of bacterial community and alkane monooxygenase gene abundance in diesel n-alkane contaminated subsurface environment under seasonal water table fluctuation

n-Alkanes, the main component of diesel fuel, are common light non-aqueous phase liquids (LNAPLs) that threaten ecological security. The subsurface from vadose zone, through fluctuating zone, to saturated zone, is a critical multi-interface earth layer which significantly affects the biodegradation processes of n-alkanes. A pilot-scale diesel contaminated aquifer column experiment has been undertaken to investigate the variations of bacterial community and alkane monooxygenase (alkB) gene abundance in these zones due to water-table fluctuations. The n-alkanes formed a layer immediately above the water table, and when this was raised, they were carried upwards through the fluctuating zone into the vadose zone. Water content and n-alkanes component C10-C12 are main factors influencing bacterial community variation in the vadose zone, while C10-C12 is a key driving factor shaping bacterial community in the fluctuating zone. The most abundant bacterial phyla at all three zones were Proteobacteria, Firmicutes and Actinobacteria, but moisture-niche selection determined their relative abundance. The intermittent wetting cycle resulted in higher abundance of Proteobacteria, and lower abundance of Actinobacteria in the vadose and fluctuating zones in comparison to the control column with a static water-table. The abundances of the alkB gene variants were relatively uniform in different zones, probably because the bacterial populations harboring alkB gene are habituated to biogenic n-alkanes rather than responding to diesel fuel contamination. The variation in the bacterial populations with height due to moisture-niche selection had very little effect on the alkB gene abundance, possibly because numerous species in both phyla (Proteobacteria and Actinobacteria) carry an alkB gene variant. Nevertheless, the drop in the water table caused a short-term spike in alkB gene abundance in the saturated zone, which is most likely associated with transport of solutes or colloids from the fluctuating zone to bacteria species in the saturated zone, so a fluctuating water table could potentially increase n-alkane biodegradation function.

Thermal Catalytic-Cracking Low-Density Polyethylene Waste by Metakaolin-Based Geopolymer NaA Microsphere.

Metakaolin-based geopolymer microspheres (MGM) with hierarchical pore structures were prepared by suspension dispersion method in dimethicone at 80 °C. The hydrothermal modification of MGM was carried out at a lower temperature of 80 °C, and a NaA molecular sieve converted from metakaolin-based geopolymer (NMGM) with good crystal structure was prepared and applied in thermal catalytic cracking of low-density polyethylene (LDPE) reaction. The one-pot two-stage thermal catalytic cracking of LDPE was carried out in a 100 mL micro-autoclave under normal pressure. In this work, the optimal proportions and optimal reaction conditions of catalysts for NMGM thermal catalytic cracking of LDPE waste to fuel oil were investigated. The NMGM catalyst showed high selectivity to the liquid product of thermal catalytic cracking of waste LDPE. Under the reaction conditions of reaction time of 1 h and reaction temperature of 400 °C, the liquid-phase yield of thermal catalytic cracking of LDPE reached a high of 88.45%, of which the content of gasoline components was 10.14% and the content of diesel components was 80.97%.