Plastic wastes such as polyethylene terephthalate have recently been incorporated into coal as additives in coke manufacturing. Plastic waste results in the reduction of high-quality coal usage while protecting the environment. Using coal tar pitch as an additive in the coal blend causes an increase in fluidity during carbonization. The volatile matter released during carbonisation affects coal thermoplasticity, hence the carbon structural parameters. This paper investigates the role of polyethylene terephthalate and the mixture of polyethylene terephthalate and coal tar pitch on carbon structure formation during coal to coke transformation. The additives were blended with coking coal in 2, 3, 4, 5, and 10% wt. The results imply that incorporating coal tar pitch into the coal/ polyethylene terephthalate mixture improves the crystallite height of the resulting semi-coke. The addition of coal tar pitch and polyethylene teraphthalate blend to coking coal at a percentage below 5%wt. leads a positive impact on the crystallite height of the resulting coal char. The incorporation of coal tar pitch into the blend decreased the average interlayer spacing. At elevated temperatures, the polyethylene terephthalate in the blend causes an increase in the mean tortuosity. However, incorporating coal tar pitch into the blend led to about 3.3% decrease in mean tortuosity.

Comparative study of the carbon structure of chars formed from coal with plastic waste and coal tar pitch additives
    Abstract
    1 Introduction
    2 Experimental
        2.1 Samples
        2.2 Thermogravimetric analysis
        2.3 Carbonization experiments
        2.4 XRD analysis
        2.5 Raman analysis
        2.6 HRTEMSEM analysis
        2.7 XPS analysis
        2.8 BET analysis
    3 Results and discussion
        3.1 Thermal behavior of samples
        3.2 XRD characterization of semi-coke
        3.3 Raman characterization of semi-coke
        3.4 HRTEM analysis
        3.5 Char porosity and surface area analysis
        3.6 XPS analysis of functional groups
        3.7 Surface morphology of char
    4 Conclusion
    Acknowledgements 
    References

• Joseph Appiah(Key Laboratory for Advanced Coal and Coking Technology of Liaoning Province, University of Science and Technology Liaoning, Anshan 114051, China)
• Lu Tian(Key Laboratory for Advanced Coal and Coking Technology of Liaoning Province, University of Science and Technology Liaoning, Anshan 114051, China)
• Jinxiao Dou(Key Laboratory for Advanced Coal and Coking Technology of Liaoning Province, University of Science and Technology Liaoning, Anshan 114051, China)
• Jiawei Wang(Key Laboratory for Advanced Coal and Coking Technology of Liaoning Province, University of Science and Technology Liaoning, Anshan 114051, China)
• Xingxing Chen(Key Laboratory for Advanced Coal and Coking Technology of Liaoning Province, University of Science and Technology Liaoning, Anshan 114051, China)
• Jianglong Yu(Key Laboratory for Advanced Coal and Coking Technology of Liaoning Province, University of Science and Technology Liaoning, Anshan 114051, China, Suzhou Industrial Park Monash Research Institute of Science and Technology, and Southeast University-Monash University Joint Graduate School, Suzhou 215123, China)
• Xiuli Xu(Key Laboratory for Advanced Coal and Coking Technology of Liaoning Province, University of Science and Technology Liaoning, Anshan 114051, China, Sinosteel Anshan Research Institute of Thermo-Energy Co., Ltd, Anshan 114044, China)