MATERIAL SELECTION AND THE IMPACT ON RECYCLABILITY, GREEN PURCHASING AND CORPORATE SOCIAL RESPONSIBILITY - THE MANGANESE METAL CASE

摘要

Manganese metal is widely used as an alloying agent in the aluminum industry and is available from two distinct production processes. The environmentally preferred process uses sulfur as the catalyst and results in a typical purity of 99.9%. The other process, favored by almost all Chinese manufacturers, uses selenium as the catalyst with the result that the manganese metal contains up to 0.15% selenium but is produced at a lower cost. This has resulted in over 75% of the global market in recent years consisting of selenium-contaminated manganese. A case study demonstrates that use of this material has an impact on the recyclability of the aluminum dross and scrap, where recyclers face metal dust exposure issues and may not be aware of the selenium content that likely triggers hazardous solid waste disposal requirements. Downstream recycling is an important consideration of green purchasing and corporate social responsibility.