The Influence of Alkyl Group on Needle Coke Formation

2011 ◽  
Vol 335-336 ◽  
pp. 1433-1438 ◽  
Author(s):  
Shu Lei Song ◽  
Xiang Lin Cheng
Keyword(s):  
Coefficient Of Thermal Expansion ◽  
Average Length ◽  
Coal Tar ◽  
Coke Formation ◽  
Needle Coke ◽  
Alkyl Groups ◽  
Uniaxial Orientation ◽  
Lower Viscosity ◽  
Solidification Stage ◽  
Unit Vectors

Co-carbonization properties of toluene soluble (TS) of coal tar pitch and waste polystyrene (WPS) were studied in a tube bomb to correlate the content of alkyl groups in the mesophase pitches with coefficient of thermal expansion (CTE) and anisotropic orientation. The alkyl contents, which were increased from 12.0% to 33.3% by adding WPS into TS, improved the properties of resultant needle coke in terms of optical texture and CTE value. The anisotropic indices of average length of vectors parallel to the CTE axis and average length of anisotropic unit vectors increased from 20.8 μm to 28.4 μm and 23.4 μm to 28.8 μm, respectively, and CTE value decreased from 0.8×10-6 /°C to 0.1×10-6 /°C. Due to the increasing alkyl groups, the lower viscosity of the carbonization system favored the development of flow texture and uniaxial orientation. And the sufficient gas evolution of good timing in co-carbonization forced the uniaxial arrangement of bulk mesophase molecules at the solidification stage.

scholarly journals Study of Quinoline Insoluble (QI) Removal for Needle Coke-Grade Coal Tar Pitch by Extraction with Fractionalized Aliphatic Solvents and Coke Formation Thereof

2021 ◽  
Vol 11 (7) ◽  
pp. 2906
Author(s):  
Jung-Chul An ◽  
Seong-Young Lee ◽  
Joo-Il Park ◽  
Manyoul Ha ◽  
Joongpyo Shim ◽  
...  
Keyword(s):  
Coal Tar ◽  
Coke Formation ◽  
Polarized Light ◽  
Extraction Process ◽  
Coke Production ◽  
Coal Tar Pitch ◽  
Needle Coke ◽  
Process Yield ◽  
Anisotropic Flow ◽  
Kinetics Of

Various fractionalized solvents with different paraffinicities were adopted to maximize the efficiency of the quinoline insoluble (QI) extraction process for coal tar pitch. In addition, highly pressurized conditions combined with raised temperature (4 bar at 300 °C) were used to accelerate the reaction kinetics of the extraction process. The QI content of purified coal tar pitch was analyzed to be 0.1% at a process yield of up to 72% as a solvent with a K-factor of 10 and above was used. Purified coal tar pitch was then processed to form anisotropic coke using a lab-scale tube bombe reactor. The texture observed under a polarized light microscope showed an anisotropic flow domain, a unique morphological feature of needle coke. The additives and reaction conditions used in this study for QI extraction for coal tar pitch were found to be effective and feasible as preliminary processing in needle coke production.

Structure of anisotropic spheres obtained in the course of needle coke formation

Carbon ◽  
1977 ◽  
Vol 15 (1) ◽  
pp. 17-23 ◽  
Author(s):  
Isao Mochida ◽  
Keiko Maeda ◽  
Kenjiro Takeshita
Keyword(s):  
Coke Formation ◽  
Needle Coke ◽  
Anisotropic Spheres

scholarly journals XRD Characterization of the Structure of Graphites and Carbon Materials Obtained by the Low-Temperature Graphitization of Coal Tar Pitch

2015 ◽  
Vol 17 (2) ◽  
pp. 87 ◽  
Author(s):  
Ch.N. Barnakov ◽  
G.P. Khokhlova ◽  
A.N. Popova ◽  
S.A. Sozinov ◽  
Z.R. Ismagilov
Keyword(s):  
Low Temperature ◽  
Carbon Materials ◽  
Coal Tar ◽  
Structural Phase ◽  
Coherent Scattering ◽  
Amorphous Structure ◽  
Coal Tar Pitch ◽  
X Ray Diffraction ◽  
Needle Coke ◽  
The Individual

The structure of some commercial graphites and carbon materials (CMs) obtained by the low-temperature catalytic graphitization of coal tar pitch with iron salt, needle coke, foamed graphite as the catalysts has been studied. The study was performed using the X-ray diffraction technique with reflections from base plane and their decomposition into two components corresponding to the structural phases of graphite which have different XRD characteristics. Various CMs were compared with respect to the structural phase ratio, distance between polyarene layers in these phases, and sizes of the coherent scattering regions. The (004) reflection provided a better fit of some properties of graphites to the calculated XRD characteristics as compared to calculation from the (002) reflection. In the case of carbonization of coal tar pitch with investigated catalyst additions, prepared carbon materials have a higher degree of graphitization and a crystallite size greater than in the other case of carbonization of the individual pitch. The highest catalytic activity is shown by foamed graphite. It was found that the use of foamed graphite as the catalyst at 800-900 ºC produced carbon materials possessing a crystalline structure with interplanar spacing close to that in commercial graphites, while in the absence of catalyst the coal tar pitch material has an amorphous structure.

The effect of mechanical vibration on the structure of needle coke prepared from a modified coal tar pitch

Carbon ◽  
2018 ◽  
Vol 130 ◽  
pp. 845 ◽  
Author(s):  
Ying Wang ◽  
Ya-wei Dong ◽  
Cun-gui Zhong ◽  
Qing Cao
Keyword(s):  
Coal Tar ◽  
Mechanical Vibration ◽  
Coal Tar Pitch ◽  
Needle Coke

Carbonization of coal-tar pitch into lump needle coke in a tube bomb

1987 ◽  
Vol 22 (11) ◽  
pp. 3989-3994 ◽  
Author(s):  
Sao Mochida ◽  
You Qing Fei ◽  
Takashi Oyama ◽  
Yozo Korai ◽  
Hiroshi Fujitsu
Keyword(s):  
Coal Tar ◽  
Coal Tar Pitch ◽  
Needle Coke

Thermal Conversion Characteristics of Coal Tar Soft Pitch at Atmospheric and Elevated Pressures

2014 ◽  
Vol 1015 ◽  
pp. 467-471
Author(s):  
Li Yue ◽  
Xue Fei Zhao ◽  
Shi Quan Lai ◽  
Li Juan Gao ◽  
Jie Yang ◽  
...  
Keyword(s):  
Formation Rate ◽  
Coal Tar ◽  
Elevated Pressure ◽  
Thermal Conversion ◽  
Raw Material ◽  
Needle Coke ◽  
Consecutive Reaction ◽  
Elevated Pressures ◽  
Carbon Structures ◽  
Group Compositions

Coal tar soft pitch (CTSP) used as raw material of preparing needle coke was heat-treated at 460, 480 and 500 °C for different holding time under the pressure of 0 MPa and 0.25 MPa. The changes of group compositions such as toluene solubles (TS), toluene insolubles-quinoline solubles (TI-QS) and quinoline insolubles (QI) were mainly studies during the thermal conversion of the CTSP. The microstructure morphologies of some calcined cokes were characterized by scanning electron microscope (SEM). The results showed that the thermal conversion of the CTSP had the features of consecutive reaction, and the pressure could accelerate the conversion rate of TS and TI-QS and the formation rate of QI. The calcined coke derived from the semi-coke obtained at atmospheric pressure exhibited better and longer streamlined fiber structures than that of the semi-coke obtained at elevated pressure, while the latter possessed more compact carbon structures than the former.

scholarly journals Thermogravimetric Determination of the Kinetics of Petroleum Needle Coke Formation by Decantoil Thermolysis

ACS Omega ◽  
2020 ◽  
Vol 5 (45) ◽  
pp. 29570-29576
Author(s):  
Natalia K. Kondrasheva ◽  
Viacheslav A. Rudko ◽  
Jorge Ancheyta
Keyword(s):  
Coke Formation ◽  
Needle Coke ◽  
Kinetics Of

Laddered-UBM Structure: Bump Reliability Improvement through Distribution of Load Concentration Points

2012 ◽  
Vol 2012 (DPC) ◽  
pp. 001827-001839
Author(s):  
Roden Topacio
Keyword(s):  
Load Distribution ◽  
Flip Chip ◽  
Solder Bump ◽  
Dielectric Film ◽  
Coefficient Of Thermal Expansion ◽  
Circuit Board ◽  
Bending Moments ◽  
Semiconductor Chip ◽  
Semiconductor Chips ◽  
Solidification Stage

Flip-chip mounting schemes have been used for decades to mount semiconductor chips to substrates. In flip-chip process, a solder bump is metallurgically bonded to the under-bump-metallurgy, also known as UBM, on a given pad of the semiconductor chip and a pre-solder is metallurgically bonded to a corresponding pad of the substrate. Thereafter the solder bump and the pre-solder are brought into proximity and metallurgically bonded using reflow. Flip-chip solder joints are subjected to mechanical stresses from a variety of sources, such as coefficient of thermal expansion mismatches, ductility differences and circuit board warping. Such stresses can subject the conventional UBM structure to bending moments specially during the flip-chip reflow solder solidification stage where the bump is still unprotected by the underfill. The effect is somewhat directional in that the stresses tend to be greatest nearer the die edges and corners and fall off with increasing proximity to the die center. The bending moments associated with this so-called edge effect can impose stresses on the dielectric film beneath the UBM structure that, if large enough, can produce fracture. This paper will discuss the load distribution on a conventional UBM structure due to the bending moments and how the Laddered-UBM structure attempts to overcome or reduce the effects of these bending moments. Contrary to conventional methods where stress concentration points are eliminated, the Laddered-UBM is designed to strategically increase the number of load concentration points along the UBM structure. With the increased number of load concentration points, the stress along the UBM is distributed more evenly which effectively reduces the stress at any given point thus preventing a single large enough stress to cause dielectric fracture. Theoretical analysis and experimental data including reliability results on both the conventional UBM structure and the Laddered-UBM structure will be presented and discussed in this paper.

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