Tar Oil Research Articles

Investigation of the bond between bamboo and ribbed steel reinforcements and the surrounding concrete by pull-out test

Traditional housing did not use expensive materials like steel reinforcement, yet some have outlived sandcrete or mud-brick housing. One means to build at a low cost is to supplement high-cost materials with low-cost types, which have comparable strength. This study compares the bond between bamboo (Bambusa vulgaris and Bambusa vittata) reinforcement as well as ribbed steel enforcement and the surrounding concrete by pull-out test. Bamboo specimens were split and cut into the dimensions of 600 mm × 20 mm ×10 mm. Sixty (60) samples of each of the two varieties were prepared, thirty (30) were coated with tar oil as waterproof agent to a length of 200 mm and embedded into fresh concrete samples and allowed to cure, while another 30 did not receive any coating. Thirty (30) specimens of 12.5 mm diameter of ribbed steel rods of length 60 mm were used as control Materials for the pull-out test were also embedded in the centre of 150 mm concrete cubes and left to cure for 28 days. The load required to pull the steel rods from concrete (5.49±0.22 kN) was greater than those for both coated Bambusa vulgaris and Bambusa vittata (1.67±0.11 kN – 1.67±0.12 kN) and uncoated Bambusa vulgaris and Bambusa vulgaris vittata (2.04±0.14 kN– 2.14±0.19 kN) bamboo. The differences were significant (p<0.05). The pull-out was also conducted in conformity with the Bureau of Indian Standard (IS) 2770: 1997.

Analysis of the co-hydrogenation process of coal tar and kitchen waste oil based on reaction kinetics model

Kitchen waste oil (KWO) and coal tar (CT) are two commonly used alternatives to crude oil for fuel production through hydrogenation. If these two raw materials can be co-hydrogenated, it will help broaden the company's sources of raw materials. Therefore, in order to reveal the positive and negative impacts of the co-hydrogenation process of these two materials and to conduct a quantitative analysis of these phenomena, co-hydrogenation experiments of CT and KWO were completed in this study. The reaction kinetics parameters of the co-hydrogenation reaction were calculated. Experiments have shown that co-hydrogenation with coal tar hydrogenation products (CTHP) can increase the hydrogenation efficiency of KWO by approximately 1.5 %. This promoting effect is mainly attributed to the hydrogen-supplying properties of compounds such as tetralin and hexahydro naphthalene present in the CTHP. Through a combined model of reaction kinetics and thermodynamics, it is calculated that the activation energy of KWO hydrodeoxygenation under the action of catalysts is 50.936 kJ·mol−1, while under the action of CTHP hydrogen supply, it is 148.429 kJ·mol−1, and this promoting effect accounts for 19.3 % of the total reaction (as deduced from comparing reaction rate constants). The experimental data presented in this paper and the calculated reaction parameters can provide a basis for design improvements in technology.

Plant Design for the Production of Propylene Oxide by Isopropylbenzene 2-phenylpropane, or (1-Methylethyl) Benzene (Cumene)

Cumene is a colorless, volatile liquid with a gasoline-like odor. It’s also known as isopropylbenzene, 2-phenylpropane, or (1-methylethyl) benzene. It’s a natural component of coal tar and crude oil, and it can also be employed in gasoline as a blending component. Cumene hydroperoxide is produced by oxidizing cumene with benzene and propylene in the presence of air. As a result, the cumene hydroperoxide is changed to cumyl alcohol, which is then transformed to propylene without the use of oxygen. Propylene oxide is an organic compound produced through various methods such as the cumene process and the hydroperoxide process. The cumene method is preferred due to its low by-product production and high market value of co-products. The reactive distillation process is a feasible method for producing propylene oxide with high purity and reduced costs. Future work includes optimizing processes, developing new catalysts, and improving efficiency. Propylene oxide has practical applications in the production of polyurethane foams, coatings, adhesives, polyether polyols, and propylene glycols.

ECONOMIC EFFICIENCY OF THE PRODUCTION OF BIOCHAR AND SOLID FUEL BASED ON BIOCAL

Useful disposal of industrial waste and biomass remains is increasingly relevant for Ukrainian enterprises. The purpose of this article is to find additional opportunities for the production of products with greater added value by processing waste and biomass residues to biochar. World prices for biochar are quite high, much higher than for the use of biocoals as fuel, and are around 800 EUR/t, maximum up to 1,800 EUR/t. The main technical characteristics and price offers of equipment for the production of biochar from nine manufacturers from China, Germany, Finland, Norway and the Netherlands were analyzed. The results of feasibility study of the biochar production from sunflower husks on a technological line with an input productivity of 5 t/h for one of the Ukrainian vegetable oils production plants are presented. As the main equipment, a drum-type pyrolyzer heated by synthesis gas, formed during the thermochemical decomposition of biomass, was considered. Byproducts of production are also bioacetic acid and tar oil. The financial indicators in the case of biochar export are attractive enough for implementation. The estimated simple payback period when using granulated husk was about 4 years at a price of biochar of 650 EUR/t and less than one year at a price of 800 EUR/t. When using non-granulated husk, the simple payback period was about 3 years, even at the price of biochar of 450 EUR/t. Possible risks for implementation are the uncertainty regarding market demand and sales opportunities for biochar, quality requirements and the ability of the considered equipment to provide them, insufficient information regarding biochar yield from various biomass, as well as the lack of experience. Enterprises interested in the implementation of such a project are recommended to conduct trial processing of a batch of their raw materials on similar equipment in advance, to determine the share of biochar yield and its quality characteristics, to search for potential buyers to discuss quality requirements and possible prices.

Comparative Chemical and Biological Analysis of Wood and Tar Essential Oils from Cedrus atlantica and Juniperus oxycedrus in Morocco

Comparative Chemical and Biological Analysis of Wood and Tar Essential Oils from Cedrus atlantica and Juniperus oxycedrus in Morocco

Evaluation of the capability of oil specific discrimination in detection dogs

Dogs are used for oil detection to support spill remediation and conservation, but little is known about the effects of weathering and aging of oil odorants on dogs’ ability to generalize and discriminate unweathered oil from aged/weathered tar ball oil. Three dogs were trained to detect unweathered oil odorant using a three-alternative choice procedure and automated olfactometers. We evaluated dogs’ ability to discriminate unweathered target oil from four different weathered/tar ball samples. All three dogs successfully discriminated the unweathered target oil from the four nontarget weathered oils with an accuracy of 96%, 97%, and 100%. After the oil discrimination test, dogs’ ability to discriminate unweathered target oil from novel natural odorants on a beach (plastic bottle lid, bird feathers, and rocks) was tested in a novel discrimination test yielding an accuracy of 95%, 100%, and 100%. These data suggest dogs are successful in discriminating unweathered oil from weathered oil with explicit training.

The interactions of plastic with tar and other petroleum derivatives in the marine environment: A general perspective

Plastic and oil pollution are closely linked to our dependence on petroleum derivatives. Their excessive use and inefficiencies in their management, have led to negative impacts on marine ecosystems since their very introduction. Agglomerates of tar, plastic, paraffins, and other petrochemicals and oil derivatives with naturally occurring materials, are increasingly widespread in coastal environments, stalling as an iconic and readable sign of environmental degradation. Starting from a historical review of the available reports on the occurrence of similar aggregates dating back to 1971, we highlight how most of these observations are based on the morphological description of the petroleum residues with no chemical fingerprinting and are mainly related to materials stranded on the coastline, with few and unclear indications for the open sea. We discuss here a list of scientific questions and knowledge gaps, that need to be examined by future studies.

The Effect of Adding Pine Tar Oil and Petrosin as Tackifier Ingredients on The Quality of Liquid Rubber Compound-based Adhesives

This research is focused on the development of adhesives through the utilization of different types of tackifiers. The primary raw materials employed comprise 60% concentrated latex, which is subsequently blended with additives that have been dispersed, including KOH as a stabilizing agent, stearic acid and ZnO as activators, BHT as an antioxidant, CaCO3 as a filler, MBTS (Mercaptobenzothiazole disulfide) and TMTD (Tetramethyl Thiuram Disulphide) as accelerators, and sulfur as a vulcanizing agent. This research explored two specific variations of tackifiers: pine tar oil and petrosin. The characterization of the adhesives encompasses an analysis of acidity (pH), viscosity, adhesive strength, functional group analysis using FTIR, thermal properties, and XRD. The research findings showed that the optimal conditions were achieved in the third variation of the adhesive, with the same ratio of pine tar oil tackifier and petrosin of 4 grams each. In this particular variation, adhesives conforming to the SNI 12- 7195-2006 standards were produced, displaying an adhesion strength of 1.506 N/mm, a viscosity of 1075 cP, and a pH level of 4.6. Furthermore, thermal testing results reveal that the adhesive created with tackifier (V3) exhibits thermal resistance up to 350°C, a glass transition temperature of 354°C, and a melting point of 378°C.

Utilisation of coal tar naphthalene oil fractions for the synthesis of value-added chemicals: alternative paths to mono- and di-methylnaphthalenes

This study investigates the utilisation of coal tar naphthalene oil fraction (CTNOF), an economical by-product derived from the iron-steel industry, for the production of valuable chemicals, with a particular focus on methylnaphthalenes (MNs) and dimethylnaphthalenes (DMNs). Of specific interest is 2,6-dimethylnaphthalene (2,6-DMN), a pivotal component in the manufacture of polyethylene naphthalate (PEN). The intricate and costly nature of 2,6-DMN production currently poses challenges to the commercial viability of PEN. This study provides the potential heterogeneous reaction pathways for the synthesis of MNs and DMNs via methylation, disproportionation, and isomerisation of CTNOF. The utilisation of CTNOF was investigated in a laboratory-scale fixed bed reactor operating at atmospheric pressure using a mixture of CTNOF: methanol having 1:5 mass ratio over HBeta zeolite catalyst at a temperature of 400 °C and weight hourly space velocity of 2 h−1. The results reveal the successful methylation of CTNOF over the HBeta zeolite catalyst, initially achieving high naphthalene conversion, particularly into 2-MN. This highlights the potential of CTNOF as an alternative feedstock for the production of value-added chemicals. While naphthalene conversion initially reaches 99 wt% within 0.5 h of operation, it gradually decreases to approximately 10 wt% over extended run times. Notably, coke deposition significantly deactivates the HBeta zeolite catalyst during CTNOF methylation, impacting naphthalene conversion. A substantial proportion of naphthalene compounds convert to methylnaphthalenes early in the reaction, predominantly 2-MN, increasing from 14 wt% (in CTNOF feedstock) to 87 wt%. Among DMNs, selectivity for 2,6-DMN, 2,7-DMN, 1,3-DMN, and 1,7-DMN increases, while other DMN isomers exhibit a sharp decrease in selectivity. The distribution of 2,6-triad DMNs rises from 38 wt% in feedstocks to 52–55 wt% with extended reaction times, attributed to MN conversion to DMNs and potential isomerisation from other DMNs. This study underscores the feasibility of using CTNOF for the direct synthesis of valuable chemicals, specifically 2,6-DMN and 2-MN, through methylation over HBeta zeolite catalysts. However, it emphasises the critical role of residence time in coke deposition and the need for optimisation, particularly regarding this parameter, to ensure the efficiency of this catalytic process.

Comparative study between coal tar pitch and lower polycyclic aromatic hydrocarbon (PAH) alternative binders for use in taphole clays

The use of alternative low polycyclic aromatic hydrocarbon (PAH) binders in taphole clays is essential due to health and environmental concerns associated with PAHs. Binders that could potentially substitute for highly-temperature coal tar pitch (CTPht) or coal tar (CTht) in taphole clays were investigated. These include coal tar pitch blend, low PAH coal tar pitch, petroleum-based binders and wood-based tars from various sources. The binders were characterized according to chemical composition, with an emphasis on the identification of 16-EPA-PAH (well-known carcinogens), as well as rheology and volatilization behaviour. The alternative binders were ranked according to the analytical results, with the coal tar reference binder, CTht, serving as the benchmark. Beechwood tar (Tar-BW) and crude waxy oil (CWO) showed the most favourable results for replacing CTht in taphole clay. Both have higher viscosities than CTht, lower BE-values (indicating lower toxicity), and higher degrees of mass loss over a wider temperature range.

Slurry-Phase Hydrogenation of Different Asphaltenes to Liquid Fuels on Dispersed MoS2 Nanocatalysts.

Asphaltene, the most complex and recalcitrant fraction of heavy oil, was investigated in this study to gain new insights into its structure and reactivity. Two types of asphaltenes, ECT-As and COB-As, were extracted from ethylene cracking tar (ECT) and Canada's oil sands bitumen (COB), respectively, and used as reactants for slurry-phase hydrogenation. Characterization of ECT-As and COB-As was carried out by a combination of techniques, including XRD, elemental analysis, simulated distillation, SEM, TEM, NMR, and FT-IR, to gain insights into their composition and structure. A dispersed MoS2 nanocatalyst was used to study the reactivity of ECT-As and COB-As under hydrogenation conditions. The results showed that under optimal catalytic conditions, the vacuum residue content of hydrogenation products could be reduced to less than 20%, and the products contained over 50% light components (gasoline and diesel oil), indicating that ECT-As and COB-As were effectively upgraded. The characterization results indicated that ECT-As contained a higher aromatic carbon content, shorter alkyl side chains, fewer heteroatoms, and less highly condensed aromatics than COB-As. The light components (gasoline and diesel oil) of ECT-As hydrogenation products mainly consisted of aromatic compounds with 1-4 rings, with the alkyl chains mainly composed of C1-C2, while light components of COB-As hydrogenation products were mainly composed of aromatic compounds with 1-2 rings and C11-C22 paraffins. The characterization of ECT-As and COB-As and their hydrogenation products revealed that ECT-As was an "archipelago type" asphaltene, composed of multiple small aromatic nuclei interconnected through short alkyl chains, while COB-As was an "island type" asphaltene, with long alkyl chains connected to aromatic nuclei. It is suggested that the structure of asphaltene has a significant impact on both its reactivity and product distribution.

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

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

Investigation of the extraction ability and mechanism of environmentally friendly ionic liquids for phenol in the model oil

The large number of phenolic compounds contained in coal tar and coal-converted oil seriously increased their cost of processing and transportation difficulties, so methods for efficient separation of phenolic compounds is of great industrial significance. Based on the flexible designability of ionic liquids, hydroxyl functional group that can interact with phenol were introduced into ionic liquid’s cations, eight ionic liquids were synthesized and their separation properties of phenol in model oil (methylbenzene) were studied. Cations of these ionic liquids have a significant influence the phenol extraction efficiency, which follows the order: [Ch]+ > [HEMIM]+. But the anions show a relatively small influence, and the order is: [Pro]- > [Lac]- > [Gly]- > [Ac]-. Other effects such as extraction temperature, molar ratio of phenol to ILs, extraction time and other factors on the extraction efficiency and distribution coefficient were investigated, also the optimum parameters were obtained. Hydroxyl modified ionic liquids showed good extraction performance for phenol, and the choline propionate ionic liquids showed the best separating capacity and were selected as the best extractant. The extraction performance was analyzed by 1H NMR and FT-IR spectra analysis. Hydrogen bond was confirmed to be one of the extraction mechanisms and we found that there was an optimal distance between the cation and anion of ionic liquids to form hydrogen bonds with phenol, also the π-π interaction between imidazole ring and benzene ring in phenol contributed to the extraction. In addition, the ionic liquid showed good recyclability and the regenerated ionic liquids could be reused five times with highly extraction efficiency.

Контроль якості вбирної оливи для уловлювання бензольних вуглеводнів за показником виходу коксового залишку.

Specific consumption of absorbent oil and its quality indicators are key characteristics of the benzene department, as they reflect the level of operating costs and determine the degree of equipment contamination with sediments. The thickening of coal tar absorbent oil during operation depends on the level of oil loss with crude benzene, the intensity of the oil polymerization and oxidation reaction, the degree of introduction of resinous and solid substances with coke oven gas, the intensity of coke formation under the influence of high temperatures, and the quality of the absorbent. Recently, little attention has been paid to such an integral indicator of absorbent oil quality as coke residue yield ("coking point"). Coking ability is associated with the viscosity, chemical composition and degree of oil purification, and is used mainly for petroleum oils operating at high temperatures. The relationship between the coke number and the physical and chemical properties of the feedstock can be traced by analyzing the dependence on the average boiling point of the tar fractions. An increase in the viscosity and density of the absorbent oil is reflected in an increase in the coke residue yield in a linear fashion, and a decrease in the content of lowboiling oil distillation in favor of high-boiling oil also increases the coke residue yield. The highest degree of correlation is observed in the exponential dependence of the coke number on the content of substances insoluble in toluene in the oil. The coking point of the absorbing oil is an indicator of the intensity of the oil oxidation and polymerization processes, the presence of corrosion and equipment wear products, the addition of tar and sulfurcontaining substances, and the presence of salts. The use of tar to initiate coke formation is an indicative and convenient way to comparatively assess the performance properties of fresh oil. This makes it possible to use the method of determining the yield of coke residue to assess the tendency of fresh oil to form sediments in equipment. Keywords: absorbent oil, coke residue yield, fractional composition, group composition, dependence, correlation degree. Corresponding author: A.L. Bannikov, e-mail: artiksmartik@gmail.com

Оценка возможности получения мезофазы при термообработке различных видов углеводородного сырья

The possibility of obtaining anisotropic pitches by heat treatment of various types of petroleum feedstock is shown - isotropic pitches from heavy pyrolysis tar and heavy catalytic cracking gas oil. The dependences of the change in the group compositionof the heat treatment residues on the duration of isothermal exposure, the correlation between the components insoluble in toluene and quinoline, have been established. Features of the optical texture of the heat treatment residues of isotropic petroleum pitches of various origins are revealed.

THE EFFECT OF ADDITIVES CONTAINING POLYCYCLIC ARENAS ON THE FORMATION OF THE PROPERTIES OF BITUMEN BINDER IN THE PROCESS OF THEIR JOINT OXIDATION WITH OIL TAR

The results of the study of the effect of polycyclic aromatic hydrocarbons (PAHs) on the efficiency of the process of oxidation of oil tar into bitumen are presented. By-products of oil refining were used as additives to tar: the residue of heavy pyrolysis resin (OTSP) and 2 samples of extracts (MAE-1; MAE-2) isolated from extracts of selective purification of oil distillate VD-3 using a polar solvent N-methylpyrrolidone containing 10 wt.% ethylene glycol. One of the extracts, MAE-2, was obtained from an oil extract pretreated with microwave radiation. Additives were injected into the tar at 70 ℃ in an amount of 10 wt.%. The hydrocarbon system was oxidized with air oxygen for 6 hours at a temperature of 220 ℃. Based on the analysis of the properties and group, structural and group compositions of oxidized bitumen binders, it was found that the content of benzene resins in the binder increases (~ 2.5 times) and asphaltenes (by 3 wt.%) during the oxidation of the mixture of MAE-1 + OTSP. When the mixture of MAE-2 + OTSP is oxidized, the content of benzene resins and asphaltenes in the binder decreases. The observed changes in the compositions of the oxidation products of mixtures of MAE + OTSP are preserved during the oxidation of tar + systems (MAE + OTSP). At the same time , the conditional content of aromatic structures according to the data of the IR spectrometric analysis in the oil component of the oxidized tar + system (MAE-2+OTSP), as well as poly-substituted polycyclic aromatic structures, is almost 2 times higher than for the oil component of the oxidized tar + system (MAE-1+OTSP). As a result, the oxidation of tar mixtures with additives containing polycyclic arenas improves the quality of the target product by increasing the content of asphaltenes and aromatic structures in the aromatic oil component.

Separation and analysis of six fractions in low temperature coal tar by column chromatography

The low temperature coal tar (CT) is taken as the raw material, and the extraction and column chromatography are used for detailed and accurate characterization in this paper. The n-heptane soluble fraction (CT-HS) and insoluble fraction (CT-HI) were obtained by n-heptane Soxhlet extraction. The extraction rate of CT-HS reached 92.79% (mass), which indicated that there are few heavy compounds in it. Further, different solvents (methylbenzene, benzene, ethyl acetate, methylbenzene-ethanol) were used to elute CT-HS by chromatographic column to obtain five fractions (saturates, aromatics, heteroatoms, phenolics and resins, named CT-SA, CT-AR, CT-HE, CT-PH, CT-RE, respectively). The yields of CT-SA, CT-AR, CT-HE, CT-PH, CT-RE are 42.12%, 10.43%, 2.19%, 9.50% and 6.63% (mass), respectively. Gas chromatography-mass spectrometry analysis of eluting components show that alkanes are the main components in CT, followed by polycyclic aromatics, and the corresponding fractions are CT-SA and CT-AR, respectively. The relative content of aliphatics in CT-SA is 76.93%, and the relative content of aromatics in CT-AR is 75.05%. This separation technology effectively separates and enriches different components in CT, and the activation energy required for the pyrolysis process of a single eluting fraction is lower than that of CT, which is expected to provide an important reference for the separation, analysis and conversion of complex oil products such as coal-oil co-processing products, coal tar and other complex heavy carbon oil products.

Performance Evaluation of Green Cushion Gum Composite Formulated Based on Hybrid Filler and Curing System

Cushion gum is a type of rubber composite material used as adhesive in the manufacture of retread tires. Therefore, cushion gum should have good processability and mechanical characteristics, particularly tensile property, and adhesion strength. The effect of hybrid filler and curing system on the performance of green cushion gum composite was investigated to determine the appropriate green cushion gum formula designed at a laboratory scale. The content of CB N330/lignin in hybrid filler was arranged at 40/10 phr and 50/10 phr. Meanwhile, the curing system was performed semi-efficient (CBS/S 1.6/1.6 phr) and conventional (CBS/S 1.6/2.2 phr). Green cushion gum composite was also formulated using pine tar oil as a bio plasticizer. Referred to the curing characteristic and mechanical property test result, it showed that green cushion gum composite formula coded by RF1 which composed of CB N330/lignin as 50/10 phr and applied conventional curing system which ratio of CBS/S as 1.6/2.2 phr was regarded as the acceptable combination in designing green cushion gum composite formula. Higher CB N330 loading in hybrid filler composition and conventional curing system attributed to the relatively high crosslink density indicated by MH-ML value. Consequently, green cushion gum composite was obtained using the RF1 formula that has a better optimum curing time accompanied by good tensile property and adhesion strength. The composite was also comparable to conventional commercial cushion gum.

Tar Oil Formulation as 95 % Soluble Concentrate and Evaluation of Its Insecticidal Efficacy against Cotton Leafworm, Spodoptera littoralis and Cutworm Agrotis ipsilon (Lepidoptera: Noctuidae)

Tar Oil Formulation as 95 % Soluble Concentrate and Evaluation of Its Insecticidal Efficacy against Cotton Leafworm, Spodoptera littoralis and Cutworm Agrotis ipsilon (Lepidoptera: Noctuidae)

Co-carbonization of ethylene tar and fluid catalytic cracking decant oil: Development of high-quality needle coke feedstock

In this study, ethylene tar (ET) and refined ethylene tar (ETR) were co-carbonized with fluid catalytic cracking decant oil (DO) to prepare needle coke. The compositions and functional group changes of the blended feedstocks were revealed by Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance. Besides, the carbonization behavior of feedstocks was determined in terms of coke optical observation, carbonized gas composition, and escape rates. The morphology and performance of needle coke were evaluated by scanning electron microscopy and coefficient of thermal expansion. The results showed that the blending of DO to the feedstocks increases the H/C ratio and the content of alkyl and naphthenic structures, which improves the growth and development of the mesophase. However, the coke derived from co-carbonization of ET and DO exhibits a clear separation interface between different optical textures. Further investigation revealed that a large amount of asphaltenes in ET polymerized rapidly into mosaic texture, which hardens prematurely and cannot coalesce with the domain texture subsequently generated by DO. The compatibility of blending ETR and DO for co-carbonization improves significantly after ET is refined to remove asphaltenes. In addition, sufficient gas flow derived from DO promotes the optical microstructure of the resultant cokes by a transition from domain texture into acicular flow type. The synergistic effects between ETR and DO result in the actual CTE and yield of needle coke being lower than the theoretical ones. The CTE of NC-ETRDO50 is lowered to 1.62 × 10-6/°C, being almost the same as that of NC-DO, and the production growth of NC-ETRDO50 is even higher by 7.32% compared with that of NC-DO. Therefore, high-quality needle coke with high production was prepared from low-cost heavy oils.