Natural gas pyrolysis produces hydrogen and solid carbon at high temperatures in an oxygen-free environment. This study has evaluated the characteristics of solid carbon obtained from the pyrolysis of methane and natural gas by using molten tin (Sn) at 900–1000 °C. Material characterization outcomes revealed that solid carbon produced at 1000 °C has a spherical morphology. At this temperature, methane and natural gas pyrolysis have resulted in the arrangement of nanocrystalline carbon spheres with average sizes of 635 and 287 nm, respectively. Similarly, pyrolysis at 900 °C and 950 °C has yielded nanocrystalline carbon featuring diverse morphologies such as spheres, fibrous, and irregularly shaped particles. Thermogravimetric analysis revealed that solid carbon products obtained from methane and natural gas pyrolysis at 1000 °C have higher thermal stability compared to commercial carbon black N991. Surface area analysis has indicated that solid carbon from natural gas pyrolysis at 1000 °C has 4.3- and 5.3-times higher surface area compared to the commercial carbon black N991 sample and graphite flakes, respectively. These findings offered insights into optimizing pyrolysis reactor design and operation to generate valuable solid carbon by-products while maximizing hydrogen production.

Temperature effects on the properties of solid carbon from natural gas pyrolysis in molten tin
    Abstract
        Graphical abstract
    1 Introduction
    2 Experimental setup
        2.1 Materials
        2.2 Experimental testbed
        2.3 Solid carbon cleaning procedure
        2.4 Characterization techniques
    3 Results and discussion
        3.1 Scanning electron microscopy
        3.2 Raman spectroscopy
        3.3 Transmission electron microscopy
        3.4 X-ray diffraction spectroscopy
        3.5 Energy-dispersive spectroscopy
        3.6 Thermogravimetric analysis
        3.7 Nitrogen gas adsorption analysis
    4 Summary
    5 Conclusions
    Acknowledgements 
    References

• Shashank Reddy Patlolla(Clean Energy Research Centre, The University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada)
• Amir Sharafian(Clean Energy Research Centre, The University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada)
• Kyle Katsu(Clean Energy Research Centre, The University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada)
• Walter Mérida(Clean Energy Research Centre, The University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada)