Coal tar pitch is a raw material that can be made from various carbon materials such as activated carbon, carbon fiber, and artificial graphite through heat treatment. In particular, it is an important raw material used as a binder and impregnated pitch when manufacturing carbon composite materials. In order to improve the physical properties of such a carbon composite material, the content of β-resin is an important factor. Although β-resin plays the role of a binder, it also corresponds to fixed carbon, so it can determine the physical properties after carbonization. In this study, we compared the physical properties of coal tar pitch various temperature ramping rate, and found through Py-GC/MS analysis that intermediate materials were generated by heteroatoms such as oxygen and nitrogen. MALDI-TOF/MS analysis revealed that these intermediate materials overlapped with the molecular weight region of β-resin. Therefore, the content of β-resin is in the following order: 430–5 (12.8 wt%), 430–10 (10.2 wt%), and 430–2 (6.3 wt%), and when 430–5 is used as a binder, the highest density appeared at 1.75 g/cm3. However, such intermediate materials undergo thermal decomposition even at temperatures above 900 °C. As a result, after carbonization, 430–5 had a density of 1.60 g/cm3, which was similar or lower than that of 430–2 (1.72 → 1.63 g/ cm3) and 430–10 (1.73 → 1.61 g/cm3). From these results, it is expected that if the heteroatom content is distributed in an appropriate amount and the heating rate is well controlled, it will be possible to maintain a high density even after carbonization while ensuring a high beta-resin content.

The effect of heteroatoms and temperature ramping rate on pyrolysis of coal tar pitch for high value of β-resin
    Abstract
    1 Introduction
    2 Experimental
        2.1 Materials
        2.2 Heat treatment of coal tar pitch
        2.3 Properties of CC composite
        2.4 Characterization
            2.4.1 Proximate analysis
            2.4.2 Pyrolysis–gas chromatographymass spectrometer
            2.4.3 Thermogravimetric analysis
            2.4.4 MALDI-TOFMS
    3 Results and discussion
        3.1 Chemical properties of pitch according to heat treatment temperature
        3.2 Thermal behavior of pitch according to temperature ramping rate
        3.3 Properties of CC composites
    4 Conclusion
    Acknowledgements 
    References

• Seungjoo Park(Hydrogen Convergence Materials Laboratory, Korea Institute of Energy Research (KIER), Daejeon 34129, Republic of Korea, Energy Engineering, University of Science and Technology (UST), Daejeon 34113, Republic of Korea)
• Seungjoo Park(Hydrogen Convergence Materials Laboratory, Korea Institute of Energy Research (KIER), Daejeon 34129, Republic of Korea)
• Song Mi Lee(Hydrogen Convergence Materials Laboratory, Korea Institute of Energy Research (KIER), Daejeon 34129, Republic of Korea)
• Gyusang Lee(Hydrogen Convergence Materials Laboratory, Korea Institute of Energy Research (KIER), Daejeon 34129, Republic of Korea, Energy Engineering, University of Science and Technology (UST), Daejeon 34113, Republic of Korea)
• Doo‑Hwan Jung(Hydrogen Convergence Materials Laboratory, Korea Institute of Energy Research (KIER), Daejeon 34129, Republic of Korea, Energy Engineering, University of Science and Technology (UST), Daejeon 34113, Republic of Korea) Corresponding author