Mapping cerium flows in China: A dynamic material flow analysis

Cerium (Ce) is the most abundant and widely used rare earth element (REE). However, its metabolism patterns and domestic demand determinants in both traditional and emerging fields remain unknown in China. This study aims to account for the cerium flows and stocks in China from 2011 to 2020 by employing a dynamic material flow analysis method. Also, the key factors that determine the final domestic demands for cerium are uncovered by using panel regression models. The results show that: (1) there is a growing surplus of Ce-containing primary products in China, which are largely imported from Malaysia and exported to Japan and the United States; (2) cerium is mainly used in traditional fields, but its consumption in both high-tech and green fields is growing rapidly. Technological progress and cerium oxide prices are determinants of cerium final demands in both traditional and emerging fields, but GDP and cerium production only affect the demands for traditional applications significantly; and (3) the in-use stocks and the End-of-Life flows of cerium are fast-growing, and the secondary cerium resource can be mostly collected from polishing powders, automobile catalysts, NiMH batteries, glass additives, and lamps. Based on these major findings and the Chinese realities, this study further proposes several policy recommendations to promote sustainable cerium resource management.