Olefin Structure Research Articles

SYNTHESIS AND PHOTOPHYSICAL PROPERTIES OF NEW DIPHENYLACRYLONITRILE-BEARING ALDEHYDES

Background: The cyano group is well-known for its strong electron-withdrawing properties, Effective in producing acrylonitrile when added to ?-conjugated alkene structures. The twisted structures of acrylonitrile help avoid the ACQ phenomenon and induce AIE properties, making acrylonitrile units important in various applications. Aims: Synthesis of acrylonitrile units via cyano aldol condensation by temperature control and study of AIE activity. Methods: The synthesis of diphenyl acrylonitrile units took place in two steps: 1- By o-arylation, linear aldehydes were synthesized, 2- Gradually adding p-ansiyl cyanide to the linear aldehydes in a round flask containing methanol and KOH. Results: Diphenyl acrylonitrile units were synthesized, and their structures were identified using IR, 1HNMR, 13CNMR, and mass techniques. The photophysical results indicated that diphenylacrylonitrile-bearing aldehyde compounds have fluorescence with a wavelength ranging between 400-500 nm and moderate AIE activity. Discussion: The prepared diphenylacrylonitrile-bearing aldehydes units showed moderate AIE activity in the aggregation state, where the fluorescence intensity increases with increasing water percentage in the THF/H2O mixture and reaches its peak at 80%. The reason lies in the fact that the cyano group forms acrylonitrile with twisted structures, which avoids ACQ and enhances the AIE properties. Conclusions: by controlling the temperature and through a facile aldol condensation, phenylacrylonitrile units were synthesized in good yields. Their photophysical properties were studied, and they were found to have moderate AIE activity.

Promotion of Metal‐Free Catalytic Coupling of Fluorinated Halogenated Hydrocarbons By a Base for the Synthesis of Difluoromethyl Heterocyclic Amines

The selective functionalization of difluoromethyl groups (‐CF2) is a promising approach and an attractive synthetic route for accessing fluorine‐containing moieties with medicinal benefits. Here, we report a case of a C‒N coupling reaction between bromodifluoropropene with heterocyclic amines, such as indole, pyrrole, and imidazole, promoted by an alkali without the use of transition metal catalysis. This reaction differs from existing methods in that it does not undergo a difluoromethylation isomerization reaction but directly retains the structure of the terminal olefin. This chemical conversion process has a wide substrate range, good functional group tolerance, and an ideal reaction conversion rate, making it an effective new method for the difluoropropenation of heterocyclic amines.

Comparative simulation of green finance-driven oil production and expulsion: Technological innovation with Expulsinator and traditional pyrolysis in near-natural conditions

This study explores the impact of green finance and technological innovation on oil production and expulsion by comparing the Expulsinator with traditional pyrolysis methods. The Expulsinator introduces a novel approach to simulating compound production and expulsion in natural settings, utilizing hydrous decomposition in an open pass-on mode and lithostatic compression on an intact starting point disc with an undamaged mineral framework and chemical kerogen network. In contrast, traditional decomposition methods, while valuable for assessing production dynamics, are less suitable for studying primary emigration and expulsion due to sampling damage, improper pressure settings, closed-mode burning, or waterless pyrolysis. This study aims to assess the efficacy of energy production and expulsion emulation by the Expulsinator, driven by green finance initiatives, and compare it with traditional decomposition methods. Production and evacuation behaviors were evaluated using Rock Evaluation pyrolysis, HyPy, and covered small container pyrolysis (CSVP). The Expulsinator exhibited higher asphalt discharge than CSVP, attributed to increased bitumen cross-linking during traditional pyrolysis, which favors pyrobitumen formation. Variations in alkane quantities and structures were observed due to ejection impacts and production dynamics, especially delayed ejection from chromatography. Expulsinator hydrous CSVP ratios remained at 65 %, while TOC ratios exceeded 81 %. Lower gas production was observed compared to CSVP, with higher Expulsinator TOC conversion explained by the rapid removal of produced products in the open setup to prevent reformation. The Expulsinator provides valuable data on oil and gas production suitable for computational modeling tasks, highlighting the role of green finance and technological innovation in advancing sustainable energy solutions.

Dynamic viscosity, interfacial tension and diffusion coefficient of n-hexane, cyclohexane, 2-methylpentane with dissolved CO2

In this work, n-hexane, cyclohexane and 2-methylpentane were selected to represent linear-alkane, cycloalkane and branched-alkane, respectively. Based on the dynamic light method (DLS), the viscosity, interfacial tension and diffusion coefficient of n-hexane/CO2, cyclohexane/CO2 and 2-methylpentane/CO2 systems under saturation condition were measured in order to explore the change trend of thermophysical properties of the systems with the same carbon atom number but different molecular structures. The experiments were conducted at the temperatures of 303, 343 and 383 K and at pressures up to 5.64 MPa. The expanded uncertainties（k = 2）of dynamic viscosity, interfacial tension and diffusion coefficient were 3 %, 3 % and 4.4 % respectively. The experimental results show that n-hexane and 2-methylpentane with similar molecular structure have more similar value of the properties. The effects of different alkane structures on system viscosity, interfacial tension, and diffusion coefficient were explained at the molecular level through radial distribution function, interface thickness, and CO2 coordination number. At 303.15 K and 4 MPa, the peak radial distribution function of CO2/cyclohexane is 1.845, which is greater than that of CO2/n-hexane and CO2/2-methylpentane molecules. It has been proven that the arrangement of CO2/cyclohexane is more orderly, resulting in higher viscosity and lower diffusion coefficient of the system. The interface thickness of CO2/cyclohexane is 6.13 nm, which is smaller than CO2/n-hexane (7.53 nm) and CO2/2-methylpentane (6.3 nm). The smaller the interface thickness, the more compact the structure, the stronger the intermolecular forces, and the greater the interfacial tension. At 303.15 K and 2 MPa, the number of CO2 coordination sites within 1 nm around liquid phase alkanes is 3.96, which is smaller than 4.78 for cyclohexane and 6.62 for 2-methylpentane. Prove that the coordination number is directly proportional to the diffusion coefficient and inversely proportional to viscosity and interfacial tension.

Enhanced biofuel production from Sacha Inchi wastes: Optimizing pyrolysis for higher yield and improved fuel properties

Sacha inchi waste consists of residues (SR) and shells (SS) that are processed into liquid fuel using a traditional pyrolysis process. Pyrolysis was performed at a constant heating rate of 20 °C/min and nitrogen flow rate of 100 mL/min. Before the process took place, a preliminary TGA analysis was performed and the results revealed that the appropriate pyrolysis temperature and time allowed a variation of 250–450 °C and 10–50 min, respectively. The results showed that the pyrolysis oil yields of both SR and SS increased with increasing pyrolysis temperature and time. However, the pyrolysis oil yield of SR was significantly higher than that of SS because the main component of SR contains abundant carbon from saturated fatty acids. The ANOVA method shows that the SS model is more complex and examines more terms and interactions, whereas the SR model is simpler and focuses on fewer components, but still shows significant effects, especially through temperature. The nonsignificant p-value for time in the SR model suggests that time may not have the same influence as temperature on the dependent variable. The SS pyrolysis oil was consistent and resulted in a constant calorific value and flash point between 31.10 and 32.14 MJ/kg and 120 and 124 °C, respectively. However, decreasing the O/C atomic ratio of SR pyrolysis oil from 0.92 to 0.38 influenced the increasing calorific value from 36.66 to 38.75 MJ/kg, while the H/C atomic ratio of SR pyrolysis oil was close to 2.00. This suggests that its effectiveness maintains an alkene structure that can improve fuel efficiency. The molecular formulae of the SS pyrolysis oil were CH16N0.04O7 and that of SR pyrolysis oil was CH2.2N0.08O0.45.

High valuable wax from multilayer film packaging wastes using solid catalyst via pyrolysis process

Multilayer film packaging (MLP) waste was decomposed completely at 500 °C. Catalysts were employed to convert residue polymer to waxes via pyrolysis at 500 °C. The activities achieved from using mordenite (Si/Al = 10), H-ZSM-5 (Si/Al = 25), MCM-41, and Al-MCM-41 (Si/Al ratio of 25, 50, and 75) catalysts were studied. The yield and property of the wax were improved with the use of the catalysis with various acidity and porous structure. The low yield of the waxes, when using mordenite and H-ZSM-5 catalysts, was caused by the microporous structure and strong acidic properties of the catalysts resulting in larger amount of gas production. The MCM-41 catalyst modified with various aluminum content raised the wax yield to 60 %. Al-MCM-41(50) produced the largest amount of wax when compared to Al-MCM-41(25), Al-MCM-41(75), and MCM-41. The mild acidity and mesoporous structure of Al-MCM-41(50) significantly enhanced the paraffins structure of the obtained waxes over other structures, while lower Si/Al ratios favored the conversion of paraffins toward olefin structure. The pyrolysis of MLP with Al-MCM-41(50) produced paraffins and olefins with the middle carbon ranging (C11-20) which were similar quality to pharmaceutical grade of petroleum wax. The spent catalysts of Al-MCM-41 series gradually decreased in wax yield and paraffins composition during the sequential MLP pyrolysis; however, the activity of catalysts was recovered after calcination of the spent catalysts. Furthermore, the viscosity of waxes obtained from Al-MCM-41(50) was 2384 Pa.s at 25 °C similar to the viscosity from commercial petroleum jelly base of 2333 Pa.s.

Synthesis of biosurfactants from polyethylene waste via an integrated chemical and biological process

Polyethylene, as the predominant polymer produced globally, poses significant environmental challenges due to its resistance to natural decomposition. In this study, we introduce an innovative chemicalbiological approach for transforming waste polyethylene into valuable biosurfactants. Our method involves hydrogenolysis using specially designed Ru/CeO2 catalysts, which efficiently convert polyethylene into alkanes while keeping methane selectivity below 5 %. This optimization ensures maximum feed availability for subsequent microbial processes. Notably, the produced chemical intermediates are directly utilized in the biological phase, eliminating the need for intermediate processing. Gordonia sp. JW21, selected for its exceptional alkane degradation capabilities, efficiently metabolizes a wide range of alkane structures, including extended alkyl chains. The microbial process culminates in the generation of high-value biosurfactants. This synergistic strategy not only offers an effective solution for polyethylene waste management but also sets a precedent for the sustainable production of biosurfactants.

Performance of Polysulfones as Components of Ashless Antistatic Additives

Synthesis of polysulfones from individual α-olefins was investigated. The correlation between the specific electrical conductivity of diesel fuels (DF) and the structure of the initial alkene was identified. The antistatic properties of the synthesized polymers were investigated as a function of the polymer molecular weight and of the dispersant content. The low-temperature properties of DFs that contained a polysulfone as a component of an ashless antistatic additive were further determined.

Catalytic pyrolysis of straight-run light oil to light olefins: Role of molecular structure and catalytic materials

The development of straight-run light oil catalytic pyrolysis to light olefins process is an important approach of achieving the transformation and upgrading of the current oil refining industry. However, the industrialization of the catalytic pyrolysis process for straight-run light oil has been slow. Herein, we investigated the decomposition of complex straight-run light oil into different structural units and further examined their effects on light olefins production. The results indicated that the yields of light olefins cracked over MFI zeolite were about 45 % and 30 % for alkane structure and cycloalkane ring structure, respectively. Further analysis showed that the olefin structure could theoretically be cracked to 100 % light olefins, but in fact, 40 % of the light olefins were lost due to the transfer of 10 % hydrogen. Subsequently, the effects of zeolite topology and acid properties on the cracking of different structural units were further analyzed. It was found that zeolites with MTT and MFI topologies contributed to the catalytic pyrolysis of chain and cycloalkane ring structures, respectively, because appropriate pore size helped diffusion of hydrocarbon molecules and inhibited side reactions such as hydrogen transfer. Compared with MFI zeolite, the light olefins yield produced by chain structure cracking over MTT zeolite increased by 5.83 %-10.54 %. In addition, it was discovered that zeolites with total and strong acids in the range of 0.2–0.4 mmol/g and 0.1–0.2 mmol/g, respectively, were beneficial for the cracking of light alkanes in straight-run light oils to light olefins. This work provides useful insights into the fundamental understanding and development of straight-run light oil catalytic pyrolysis to light olefins process.

Purple‐Light Promoted Thiol‐ene Reaction of Alkenes

AbstractHere we present a catalyst‐free protocol for the purple light‐mediated anti‐Markovnikov functionalization of alkenes with thiols. Crucial to the generation of the thiyl radical was the formation of a key photo‐active complex. More than 30 thioether products were obtained, demonstrating tolerance towards different functional groups and scalability up to 5 mmol of alkene. Two different reaction conditions have been developed, varying both the solvent and the amount of thiol. Depending on the alkene structure, water can be used as an alternative to dichloromethane as a solvent, thus increasing the sustainability of the whole process.

Novel insight into structure and content of olefins in thermally cracked heavy oil and its saturates, aromatics, resins and asphaltenes fractions determined by 1H NMR spectroscopy

The factors leading to olefinic hydrogen signal shielding in the 1H NMR spectra of thermally cracked vacuum residue (VR) and its heavy fractions were revealed using a series of model compound systems, and the effect of olefinic hydrogen signal shielding on the determination of olefinic hydrogen content was elucidated. There were two main factors leading to the olefinic hydrogen signal shielding in the 1H NMR spectra of olefins in heavy fractions, i.e. intramolecular and intermolecular. For the olefin itself in heavy fractions, the chemical shift of the olefinic hydrogen closest to the aromatic ring was in the aromatic region rather than the olefinic region due to the π-π conjugation effect between the double bond and the intramolecular aromatic ring. Notably, the response intensity of the olefinic hydrogen signal could be weakened or even disappear due to the suppressive effect of the intermolecular aromatic structures in other polycyclic aromatic hydrocarbons (PAHs), while alkanes and monocyclic aromatics had little effect on the olefinic hydrogen signal response. Although the olefinic hydrogen signal was detected merely at about 5.30 ppm in the 1H NMR spectra of heavy fractions, these olefinic structures may be predominantly of the R─CH═CH2 type rather than the R─CH═CH─R′ type. More importantly, the measured olefinic hydrogen content of thermally cracked VR and its heavy fractions may be considerably lower than the actual content, with the measured content being only about 30–40 % of the actual content. This is mainly due to the weakening and disappearance of the olefinic hydrogen signal, coupled with the fact that the integral area of the possible olefinic hydrogen signal in the aromatic region was overlooked when calculating the total integral area of the olefinic hydrogen signal in the 1H NMR spectrum.

Relationship between molecular structure and dehydrogenation performance of cycloalkanes

Polycyclic alkanes are not only the important components of high-density fuels, but also can be used to cool the overheating parts of hypersonic vehicle through catalytic endothermic dehydrogenation reaction. However, the dehydrogenation performances of cycloalkanes with different molecule structures vary widely. Herein, we investigated the effects of cycloalkane structures, including the length of branched chains, the number of branched chains, the number of rings, and the shape of rings, on the dehydrogenation performance. The results show that cyclohexane (CH) exhibits the best dehydrogenation performance (600 °C, 3 MPa) with >99% conversion, >99% benzene selectivity, and highest total heat sink of 4.47 MJ/kg. The branched chains, ring number and five-membered rings all have negative effects on dehydrogenation. Among them, the number of rings has the minimum negative impact. Moreover, we correlated the density, volumetric net heat of combustion (NHOC) and heat sink with the molecular structure of the cyclic alkanes and found that the polycyclic alkanes with low H/C ratio and high M have both high density, high volumetric NHOC and high heat sink. This work can provide guidance for development and design of advanced fuels for endothermic dehydrogenation.

Supercritical water oxidation: a breakthrough approach for remediation TNT-contaminated pink water

ABSTRACT This study aimed to optimize the operating conditions of the supercritical water oxidation (SCWO) process for 2,4,6-trinitrotoluene (TNT)-containing pink water treatment. Lab-scale SCWO experiments were performed by varying the temperature (400–600°C), reaction time (45–180 sec), and oxidant ratio (100–300%). The performance of SCWO in terms of pink water treatment was evaluated using TNT and total organic carbon (TOC) removal efficiency, SCWO effluent toxicity, and generated by-products. The results showed that as temperature and residence time increased, the TNT and TOC removal efficiency increased due to solute-solvent reaction acceleration under SCWO conditions and long contact time between organic matter and oxidant. The optimal conditions for SCWO were identified as follows: a temperature of 500°C, a reaction time of 120 seconds, and an oxidant ratio of 150%. These conditions resulted in a TNT removal efficiency of 99.9% and a TOC removal efficiency of 93.5%. The by-products analysis results showed a relationship between operating temperature and the type of by-products produced. Various compounds such as toluene, nitrobenzene, TNT isomers, naphthalene, and simple alkane structures were formed. However, above 500°C, many of these species decomposed, giving rise to octadecanoic acid and 13- Docosenamide. The microbial toxicity test demonstrated that SCWO effluents showed no toxicity for all investigated SCWO conditions, demonstrating the superiority of the SCWO method for the toxicity removal of TNT-containing pink water.

Topology Molecular Indices Relationship of Electronic Properties of N-Alkanes and Branched Alkanes

Eight electronic properties; HUMO, LUMO, HOMO-LUMO energy gap, dipole moment point-charge, dipole moment hybrid, molecular weight, heat of formation and zero-point energy of 60 normal and branched alkanes were examined using topology molecular indices. All the electronic properties were calculated using semi-empirical self-consistent molecular orbital theory. The relationship of electronic calculation properties with seven models of topology indices based on degree and/or distance were obtained in terms of their correlation, regression and principal component analysis. Most of the properties were well-modelled (r2 > 0.82) by topology molecular indices except the dipole moment point-charge and hybrid. The PCA resulted in 7 properties and 60 structures of alkanes that produced two principal components with eigenvalues of greater than 1. The first principal component explained 60.388%, while the second principal component explained 26.457%, bringing a cumulative value of 86.845% to the data variation.

Comprehensive Study of the Mechanism of the “Aromatic Nitroso Oxide–Olefin” Interaction as a Function of the Reagents’ Structure

Using reaction model systems (nitroso oxide ArNOO, Ar = Me2NC6H4 or O2NC6H4; exhaustive set of methyl- and cyano-substituted ethylenes), a detailed study of the reaction mechanism of ArNOO with unsaturated compounds was carried out using the density functional theory (M06L/6311 + G(d,p)). The reaction is preceded by the formation of a reagent complex of stacking type, which is favorable for further transformation. Depending on the structure of alkene, the reaction may proceed via two extreme mechanisms: synchronous (3 + 2)-cycloaddition (the most typical case) or one-center nucleophilic attack of the terminal oxygen atom of ArNOO on the less substituted carbon atom of the double bond. The last direction becomes dominant only under special reaction conditions: ArNOO with a strong electron-donating substituent in the aromatic ring, an unsaturated compound with a significantly depleted electron density on C═C bonds, and a polar solvent. In other cases, a different degree of asynchrony in the (3 + 2)-cycloaddition is possible; however, the main intermediate preceding stable reaction products is 4,5-substituted 3-aryl-1,2,3 dioxazolidine in any event. Both thermodynamic and kinetic arguments suggest the most probable decomposition of dioxazolidine into a nitrone and a carbonyl compound. It has been shown for the first time that the polarization of the C═C bond is a powerful factor regulating the reactivity in the reaction under study. The results of the theoretical study show excellent agreement with known experimental data for a wide variety of reacting systems.

Influence of resin on the formation and development of mesophase in fluid catalytic cracking (FCC) slurry oil

Resin is one of the key components of fluid catalytic cracking slurry oil which is the raw material to form high-quality mesophase pitch. The effect of resin variations on the formation of mesophase was investigated in this paper. The results showed when the resin addition was from 0 to 20 wt%, the formation rate of mesophase remained basically invariable, but it was beneficial to the development of mesophase pitch with higher order degree. However, excessive additions of resin (>20 wt%) sharply accelerated the formation of mesophase due to the high concentration of reactive sites in the system, which shortened the time to form pitch with mesophase content close to 100%, adversely it led to the generation of mesophase pitch with lower order degree. In addition, the approximate molecular structure model of resin was constructed by various characterization methods. The aromatic ring skeleton of resin was dominated by 3–4 ring aromatic hydrocarbons. Resin also possessed structural features such as higher aromaticity, higher N and S content, larger molecular size, longer branched chains, more cyclic alkane structures and methylene bridges, and higher concentration of reactive sites than FCC-exR. Furthermore, an explanation of the effect of resin on the formation and development of mesophase with respect to the molecular structure characteristics was presumed. This work has important implications for regulating the raw material properties of FCC slurry oil and the preparation of high-quality mesophase pitch.

Indium tin oxide etch characteristics using CxH2x+2(x=1,2,3)/Ar

For the next generation display devices, dry etching technique for indium tin oxide (ITO) used as a transparent electrode is required to obtain a highly anisotropic etch profile, and to decrease the dimensional loss after the etching. For the dry etching of ITO, the easy dry cleaning of etch byproducts attached to the chamber wall during the dry etching is also important. In this study, by using novel hydrocarbon gases mixed with Ar, such as ethane (C2H6) and propane (C3H8), the dry etch characteristics and the etch residue cleaning process have been investigated using an inductively coupled plasma etcher, and the results were compared with the conventionally investigated methane (CH4)-based gases, such as CH4 and CH4/H2 mixed with Ar. The result showed that the hydrogen in CH4/H2 both decreased the ITO etch rate, and decreased the etch selectivity over photoresist (PR). By using hydrogen-less hydrocarbon gas having the alkane structure, such as CxH2x+2 (x = 2, 3), both the ITO etch rate and the etch selectivity were increased with the increase of carbon in the alkane structure; therefore, the highest etch rate was observed for C3H8. In addition, with the increase of x in the carbon of CxH2x+2, less dimensional loss, more anisotropic etch profile, and lower surface roughness could be observed. During the etching, etch residues containing C, In, Sn, O, and H were accumulated on the chamber wall due to the low volatility of the etch byproducts; however, the etch residues formed by all three hydrocarbon gases could be successfully dry cleaned using H2/Ar plasmas through the formation of InCxHy(x < y), COx, and SnHx.

Investigation of wax inhibition efficiency based on alkane structures in model asphalt for sustainable utilization of wax inhibitors

In recent years, the wax inhibitors (WIs) are used to inhibit premature crystallization of alkane molecules in asphalt at low temperatures has yielded certain benefits. However, the method for effective and sustainable use of WIs in asphalt to avoid inefficient and expensive “trial and error” procedures has not yet been determined. In this paper, the model asphalts were established through non-waxy base asphalt doped with n-alkanes (Eicosane, triacontane and tetradecane) and isoalkane (Squalene), and the wax inhibition efficiencies and cracking resistance of model asphalt with addition of three typical WIs (poly (methyl methacrylate) (PMMA), nano-SiO2 hybrid PMMA and ionic liquid (IL) modified with graphene oxide (GO)) were directly characterized by wax precipitation temperature (WPT) and extended bending beam rheometer (Ex-BBR), double edge notched tension (DENT) and thermal fatigue tests, respectively. On this basis, the microscopic mechanism of wax inhibition was investigated by molecular dynamic simulation. The results show that the wax inhibition efficiencies are higher for the short-chain n-alkanes and ordered isoalkanes to improve the low-temperature cracking, ductile and thermal fatigue resistances more significantly, but the disordered isoalkanes and high content of long-chain n-alkanes will decrease the wax inhibition efficiencies of WIs. The WIs can increase diffusion coefficient and bond stretching, angle bending and dihedral angle torsion energies but decrease the Coulomb and van der waals (VDW) energies of wax molecules to inhibit the formation of wax crystals network. It is recommended to add WIs with higher content or efficiency for asphalts with heavy n-paraffins and low concentration of branched paraffins to inhibit wax precipitation. As for asphalts containing light n-alkanes and high concentration of branched alkanes, it is suggested to add smaller amount of WIs to save resources.

Highly Sensitive and Selective Real-Time Breath Isoprene Detection using the Gas Reforming Reaction of MOF-Derived Nanoreactors

Real-time breath isoprene sensing provides noninvasive methods for monitoring human metabolism and early diagnosis of cardiovascular diseases. Nonetheless, the stable alkene structure and high humidity of the breath hinder sensitive and selective isoprene detection. In this work, we derived well-defined Co3O4@polyoxometalate yolk-shell structures using a metal-organic framework template. The inner space, including highly catalytic Co3O4 yolks surrounded by a semipermeable polyoxometalate shell, enables stable isoprene to be reformed to reactive intermediate species by increasing the gas residence time and the reaction with the inner catalyst. This sensor exhibited selective isoprene detection with an extremely high chemiresistive response (180.6) and low detection limit (0.58 ppb). The high sensing performance can be attributed to electronic sensitization and catalytic promotion effects. In addition, the reforming reaction of isoprene is further confirmed by the proton transfer reaction-quadrupole mass spectrometry analysis. The practical feasibility of this sensor in smart healthcare applications is exhibited by monitoring muscle activity during the workout.

Solute structure effect on aromatics-alkanes extractive separation toward rational LCO upgrading

Unravelling solute effect on extractive separation of aromatics and alkanes is highly required toward its rational incorporation into economical upgrading of light cycle oil (LCO). This work systematically examines the effect of aromatic and alkane structures on extraction performance from experimental and theoretical perspectives. Liquid-liquid extraction experiments demonstrate that the distribution coefficient and extraction efficiency strongly depend on the aromatic structure, whereas the selectivity and theoretical purity of aromatics significantly rely on the alkane structure. The extraction mechanism is elucidated from interaction strength and interfacial thickness analysis using molecular dynamics simulation. The diaromatics of 1-methylnaphthalene has stronger affinity to deep eutectic solvent (DES) than the monoaromatics of tetralin, while longer alkyl-chain in hexadecane enhances its repulsive interaction with DES than dodecane. Extraction process simulation was then carried out with well-regressed parameters of NRTL thermodynamic model. Process simulation confirms that a high extraction performance can be achieved for model LCO containing more diaromatics. Therefore, it is preferable to incorporate aromatics-alkanes extractive separation into the pre-hydrotreating step of LCO upgrading process.