We produced an activated carbon using sodium-lignosulfonate, in which we investigated how the sodium salt in lignin served as the activating agent during heat treatment. Our process resulted in a product with a high specific surface area of 1324 m2/ g at 800 °C and microporous structure. During the activation process, we observed the consumption of carbon due to the dehydration reaction of NaOH and the reduction of Na2CO3 to metallic Na, which created pores through oxidation/ reduction reactions. The intercalation of metallic Na between the lattices at high temperatures formed additional pores and increased the specific surface area. Our proposed mechanism holds promise for enhancing the control of the microstructure and porosity of activated carbons through the thermal treatment of biomass.

Sodium-lignosulfonate derived activated carbon: an investigation into the role of NaOH in the activation mechanism
    Abstract
        Graphical abstract
    1 Introduction
    2 Experimental
        2.1 Preparation of activated carbon
        2.2 Structural characterization
    3 Result and discussion
        3.1 Structural properties of activated carbons
        3.2 NaOH activation mechanism
    4 Conclusion
    Anchor 12
    Acknowledgements 
    References

• Jueun Choi(Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6‑1 Kasuga‑koen, Kasuga, Fukuoka 816‑8580, Japan)
• Go Bong Choi(Korea Advanced Institute of Science and Technology, 291 Daehak‑ro, Yuseong‑gu, Daejeon 34141, Republic of Korea)
• Sol Bin Seo(Department of Polymer Engineering and Graduate School, School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong‑ro, Buk‑gu, Gwangju 61186, Republic of Korea)
• Yu Rim Choi(Department of Polymer Engineering and Graduate School, School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong‑ro, Buk‑gu, Gwangju 61186, Republic of Korea)
• Min Kang(Department of Polymer Engineering and Graduate School, School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong‑ro, Buk‑gu, Gwangju 61186, Republic of Korea)
• Yoong Ahm Kim(Department of Polymer Engineering and Graduate School, School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong‑ro, Buk‑gu, Gwangju 61186, Republic of Korea)