Rapid Low-Temperature Calcination for Producing Partially Calcined Hydromagnesite as a Novel and High-Efficient Heavy Metal Removal Agent

This research revisits the decomposition of hydromagnesite and proposes a novel heavy metal removal agent based on the partial calcination of hydromagnesite at low temperature. The proposed partially calcined hydromagnesite exhibits excellent heavy metal removal capacity and surpasses the efficacy of the direct utilization of MgO 60 times. Comprehensive characterizations demonstrate that the ultrahigh heavy metal removal capacity of partially calcined hydromagnesite stems from its high specific surface area, abundant mesopores, and the adequate exposure of massive MgO nanograins on the amorphous MgCO₃ skeleton. Overall, this research offers a novel routine to produce an efficient removal agent with significant application potential for purifying heavy metals contaminated industrial wastewater effectively, together with considerable environmental and economic benefits.