Upcycling of lignin waste to activated carbon for supercapacitor electrode and organic adsorbent

We introduce a facile strategy to upcycle lignin waste to valuable activated carbon (AC). Unlike conventional preparation processes of AC, such as high-temperature carbonization above 600 °C followed by chemical or physical activation, we synthesized AC through low-carbonization (∼300 °C), ball-milling, and thermal activation. Low-temperature carbonization effectively led to the formation of the micro-pores and simultaneously high yield. Uniform activated morphology of char lignin is achieved through a ball-milling process. The as-synthesized AC exhibited a large specific surface area of 1075.18 m 2 g −1 , high specific capacitance of 115.1 F g −1 , and excellent adsorbability of 0.23 g toluene per g activated carbon . Therefore, we believe that the presented facile strategy could lead to the realization of upcycling of lignin waste to highly useful AC.