Spent lithium-ion battery materials recycling for catalytic pyrolysis or gasification of biomass

This research work studied the pyrolysis characteristics of main biomass components (i.e. cellulose, lignin) in the presence of the spent Li-ion battery cathode (BC) enriched in transition-metals (e.g., Ni, Co). The BC with a good thermostability even at > 700 degrees C could be used as a catalyst for biomass conversion. The addition methods of BC to biomass such as one-step (directly mixing) and two-step (impregnation-drying) were comparatively studied. The two-step method had a better catalytic effect in biomass pyrolysis, contributing to the reduction of decomposition temperature and activation energy. Significantly, the two-step method had a strong catalytic effect in reducing the content of cellulose-derived sugars and increasing the content of ketones via dehydration and decarboxylation. In addition, the BC used by the two-step method had a high potential for biomass pyrolysis or gasification in promoting the catalytic cracking (i.e. H-transfer) of lignin-derived phenols (tar surrogates) to hydrocarbons and aliphatics (e.g., ketones).

Automated summary

This research found that the spent Li-ion battery cathode (BC) displayed excellent catalytic effects in biomass pyrolysis, particularly when added using the two-step method. The two-step method significantly reduced the decomposition temperature and activation energy, positively impacting the conversion products of biomass.