• Korean Journal of Materials Research
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• v.25 no.6
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• pp.279-287
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• 2015

In order to prepare anode materials for high power lithium ion secondary batteries, carbon composites were fabricated with a mixture of petroleum pitch and coke (PC) and a mixture of petroleum pitch, coke, and natural graphite (PC-NG). Although natural graphite has a good reversible capacity, it has disadvaantages of a sharp decrease in capacity during high rate charging and potential plateaus. This may cause difficulties in perceiving the capacity variations as a function of electrical potential. The coke anodes have advantages without potential plateaus and a high rate capability, but they have a low reversible capacity. With PC anode composites, the petroleum pitch/cokes mixture at 1:4 with heat treatment at $1000^{\circ}C$ (PC14-1000C) showed relatively high electrochemical properties. With PC-NG anode composites, the proper graphite contents were determined at 10~30 wt.%. The composites with a given content of natural graphite and remaining content of various petroleum pitch/cokes mixtures at 1:4~4:1 mass ratios were heated at $800{\sim}1200^{\circ}C$. By increasing the content of petroleum pitch, reversible capacity increased, but a high rate capability decreased. For a given composition of carbonaceous composite, the discharge rate capability improved but the reversible capacity decreased with an increase in heat treatment temperature. The carbonaceous composites fabricated with a mixture of 30 wt.% natural graphite and 70 wt.% petroleum pitch/cokes mixture at 1:4 mass ratio and heat treated at $1000^{\circ}C$ showed relatively high electrochemical properties, of which the reversible capacity, initial efficiency, discharge rate capability (retention of discharge capacity in 10 C/0.2 C), and charge capacity at 5 C were 330 mAh/g, 79 %, 80 %, and 60 mAh/g, respectively.

• Composites Research
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• v.33 no.6
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• pp.329-335
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• 2020

In this study, the thermo-rheological behaivors of petroleum pitches with different softening points were studied, and a B-stage phenolic resins/petroleum pitches blends were prepared by adding petroleum pitches to the phenolic resins. As a result, the petroleum pitch with different softening points decreased the fluidity of the petroleum pitch as the Quinoline insoluble (QI) content increased and showed the viscous properties of the solid. In addition, the effect of adding petroleum pitches having different softening points on the thermo-rheological properties of phenolic resins was investigated. When petroleum pitch with a high softening point was added, the fluidity of the phenolic resin was reduced, and the hardening behavior was fast. It was possible to control the curing rate and curing behavior of the phenolic resin by adding petroleum pitches of different softening points. Among them, the phenolic resin mixture to which P-Pitch 2 was added has a higher fluidity than other blends under the same curing temperature condition.

• 한국기계연구소 소보
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• s.15
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• pp.37-46
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• 1985

Properties of Precursor pitch derived from petroleum residue were studied physical and chemical analysis method for investigation of production of pitch fiber. For preparing of those precursor pitches it was carried out a temperature and time variation experiment i reactor. It was demonstrated the precursor pitch prepared in this study to have a similar properties to Ashland precursor pitch capable of bulk mesophase formation from the results of the basic analysis, that is, molecular weight distribution, coking yield, carbon content, chemical composition, etc.

• Carbon letters
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• v.16 no.3
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• pp.171-182
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• 2015

Mesophase pitch is an important starting material for making a wide spectrum of industrial and advanced carbon products. It is produced by pyrolysis of petroleum residues. In this work, mesophase formation behavior in petroleum residues was studied to prepare environmentally-benign mesophase pitches, and the composition of petroleum residues and its influence on the mesophase formation was investigated. Two petroleum residues, i.e., clarified oil s (CLO-1, CLO-2) obtained from fluid catalytic cracking units of different Indian petroleum refineries, were taken as feed stocks. A third petroleum residue, aromatic extract (AE), was produced by extraction of one of the CLO-1 by using N-methyl pyrrolidone solvent. These petroleum residues were thermally treated at 380℃ to examine their mesophase formation behavior. Mesophase pitches produced as a result of thermal treatment were characterized physico-chemically, as well as by instrumental techniques such as Fourier-transform infrared spectroscopy, nuclear magnetic resonance, X-ray diffraction and thermogravimetry/derivative thermogravimetry. Thermal treatment of these petroleum residues led to formation of a liquid-crystalline phase (mesophase). The mesophase formation behavior in the petroleum residues was analyzed by optical microscopy. Mesophase pitch prepared from CLO-2 exhibited the highest mesophase content (53 vol%) as compared to other mesophase pitches prepared from CLO-1 and AE.

• Carbon letters
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• v.12 no.3
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• pp.167-170
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• 2011

Petroleum pitch-based activated carbons (ACs) were obtained in this work from a combination of pretreatment with different amounts of potassium permanganate ($KMnO_4$) and chemical activation with potassium hydroxide. The surface characteristics of the pitch after the $KMnO_4$ pretreatment were characterized by means of Fourier transform infrared spectroscopy (FT-IR). The structural characteristics of the pitch after the $KMnO_4$ pretreatment were determined by means of X-ray diffraction. The influence of the $KMnO_4$ treatment on the textural properties of the petroleum pitch-based ACs was investigated by means of $N_2$/77K adsorption isotherms. The investigation also involved the use of the Brunauer-Emmett-Teller equation and the Dubinin-Radushkevich method. The FT-IR results show that the pretreatment promotes the formation of surface oxygen functionalities and leads to an increase of the interplanar distance ($d_{002}$) of the functional groups induced between carbon layers. Moreover, the specific surface area of the pitch-based ACs increases in proportion to the amount of $KMnO_4$ pretreatment and reaches its highest value of 2334 $m^2$/g with 2 g of $KMnO_4$ because the surface oxygen groups of the pitch act as an active site during chemical activation.

• Journal of the Korean Ceramic Society
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• v.37 no.2
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• pp.128-133
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• 2000

In this work, soft carbons produced by pyrolysis of petroleum and coal-tar pitch were used as the negative electrode for Li-ion batteries. We studeid the charge/discharge capacity and the interfacial reaction of these electrodes by constructing a half cell. Charge/discharge property was studied by a constant-current step and the interfacial reaction between the electrolyte and the surface of a carbon electrode was studied by the cyclic voltammetry. The initial charge/discharge capacity for the coal-tar pitch carbon increased exceedingly with the heat treatment temperature. On hte other hand, the capacity of the petroleum pitch carbon increased with temperature up to 1000$^{\circ}C$, thereafter decreased continuously. While the charge capacity decreased with the cycle number, the reversibility increased above 90%. In addition, the thermal stability and crystallization of petroleum and coal-tar pitches were analyzed by TGA and XRD, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.303-304
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• 2007

A comparison study of carbon coating on $LiFePO_4$ was done with two different carbon sources-petroleum pitch and Ketjen black. Raman spectroscopy and transmission electron microscopy (TEM) analysis were applied to the carbon-coated $LiFePO_4$. $LiFePO_4$ which was carbon-coated with petroleum pitch showed more uniform carbon layer and ordered carbon structure. Such uniformity and ordered structure of carbon coating layer resulted in higher initial discharge capacity and better rate capability.

• Carbon letters
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• v.3 no.1
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• pp.33-38
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• 2002

Petroleum based isotropic pitch was spun into short fiber by melt-blown spinning technology. The processing parameters chosen were air velocity, die temperature, and throughput rate of the pitch within the ranges of experimental tolerances. The fiber diameter was reduced to $6{\mu}m$ by increases of hot air velocity, and spin die temperature. Also, the fiber diameter was strongly dependent on the throughput rate of the pitch and jet speed of hot air through the spinnerets. Even fibers with $10{\mu}m$ diameter were produced at throughput rate of $0.17g/min{\cdot}hole$ and at die temperature of $290^{\circ}C$.

• International Journal of Highway Engineering
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• v.16 no.5
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• pp.9-18
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• 2014

PURPOSES : The objective of this study is to evaluate the applicability of the pitch, which is produced during SDA petroleum upgrading process, as a pavement paving material. In order for the purpose, the physical and chemical properties of the pitch are analyzed, and then the various plasticizers are applied in the pitch. METHODS : Two types of pitch are selected from oil refinery companies, which are owned the SDA petroleum upgrading process. Also, two types of asphalt binders, PG 64-22 and PG 58-22, are employed to compare with the pitch because these two types of asphalt binders are currently used as paving materials. For the chemical property of the pitch, the composition of SARA (Saturate, Aromatic, Resin, Asphaltene), the elementary composition, and the functional group are analyzed. For the physical property of the pitch, the basic material property tests, such as penetration test, softening point test, flash point test, ductility test, and rotational viscometer test, are performed. Also, the DSR (Dynamic Shear Rheometer) test and the BBR (Bending Beam Rheometer) test are conducted using asphalt binder specimens obtained by both short term aging (Rolling Thin Film Oven, RTFO) and long term aging (Pressure Aging Vessel, PAV) processes. The rheological property of each pitch type is evaluated as a function of temperatures and loading cycles. PG 64-22 asphalt binder is used as a control material. RESULTS AND CONCLUSIONS : The Pitch may not be suitable for the pavement paving material without modifications, but the pitch can be used as alternatives of modified addictive or asphalt. If low molecular component, such as saturate and aromatic components, are added in the pitch based on the development of various plasticizers, it has a strong possibility for the pitch to be used as a alternative. However, in order to verify the performance property of the pitch, further research is needed.

• Carbon letters
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• v.15 no.3
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• pp.162-170
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• 2014

Pitch is an attractive raw material for carbon fiber precursors due to its low cost stemming from its availability as a residue of coking and petroleum processes. Ford Motor Company reported a carbon fiber target price of $11.0/kg by using a fast cycle-time manufacturing method with carbon fiber in an inexpensive format, allowing for an average retail price of gasoline of $3.58/gallon. They also recommended the use of carbon fiber with strength of 1700 MPa, modulus of 170 GPa, and 1.5% elongation. This study introduced a ca. $5.5{\mu}m$ carbon fiber with 2000 MPa tensile strength obtained from a precursor through simple distillation of petroleum residue. Petroleum pitch based carbon nanofibers prepared via electrospinning were characterized and potential applications were introduced on the basis of their large specific surface area and relatively high electrical conductivity.