Establishment of green graphite industry: Graphite from biomass and its various applications

Resource- and energy-efficient biomass exploitation for green graphite production is one of the most effective strategies for satisfying graphite demand while minimizing energy consumption and carbon emissions. This study investigated green graphite production from biomass waste and its applications to establish a green graphite industry. Biomass pyrolysis and catalytic graphitization of biochar were studied first to produce green graphite. The optimized green graphite exhibited a reversible capacity of 264 mA h/g and 97% capacity retention over 100 cycles in a half-cell. Green graphite electrodes with a resistivity lower than 5 mu omega m were fabricated by using organic fraction bio-oil as a green binder. Other green graphite applications, including printing, conductive printing, pencils, and refractories, were also achieved. The overall process of graphite anode and electrode synthesis from biomass waste and short-rotation energy crops was modeled. Approx. 95 kg of battery graphite or 109 kg of metallurgical graphite electrodes can be produced per ton of biomass with low primary energy consumption and carbon footprint. Prominently, the modeling result and life cycle assessment demonstrated that, for the production of battery graphite from biomass waste, net-negative-CO2 emissions (-0.57 kg CO2-eq/kg graphite powders) with net-negative-primary energy consumption (-28.31 MJ/kg graphite powders) was achieved.