Challenges and solutions of chemical treatments in the utilization of urban mines

Abstract

Considering the growth of the concerns about environmental problems and resource security in recent years, we have to utilize secondary resources. Japan, which has few natural resources, has accumulated metal resources within its society as an “urban mine” through the manufacturing and utilization of a wide variety of products. Its volume can be comparable to that of resource-rich countries, and actively utilized in these days. However, because of the different properties of “ores” extracted from urban mines and natural mines, there can be significant differences in their behaviors in the treatment processes, especially when chemically processed, and in the performance of the final product, which obstructs the utilization of urban mines. In this paper, the author summarizes an overview of the current state of urban mine utilization for representative metals, including its challenges. In addition, the development of new methods currently underway, focusing on precious metals, will be introduced.