Extraction and electrochemical lithium storage performances of double-spheroid manganous carbonate from graphene production waste effluent

According to the “double carbon” targets and circular economy, various wastes must be recycled as much as possible. Therefore, manganous ions in the waste effluent from graphene production were extracted with Na₂CO₃ as the precipitation agent by one-step chemical reaction, forming light yellow MnCO₃ powder. Meanwile, its electrochemical lithium storage properties were studied. The results show that the removal rate of manganous ions is 99.9% and the recovery rate of MnCO₃ is 92.6%. The extracted MnCO₃ powders consist of many double spheroids with a particle size of 0.5-1.5 μm, which belong to the hexagonal crystalline. After cycling for 300 cycles at 0.5 A/g and 1.0 A/g, the corresponding reversible capacity is maintained at about 570 mAh/g and 418 mAh/g, respectively. This article provides a new idea for the recovery of graphene industrial wastewater, helping to reduce environmental emissions.