A Study of Electrochemical Recycle for Noble Metals in PEFCs

Introduction In 2009, residential cogeneration system using polymer electrolyte fuel cells (PEFCs) was released in Japan, and it is anticipated that more than the 2.5 million systems will be spread in 2030. Since a lot of noble metals such as platinum and ruthenium are used in the PEFCs, it is important to establish recycle methods for the metals. According to our previous studies, almost the all platinum and platinum alloy incorporated into carbon paper could be dissolved electrochemically using potential fluctuations within a few minutes. However, the environmental burden of the method was larger than that of a chemical method using aqua regia mainly due to the enormous power consumption. The objective of this study are to reduce the power consumption of the electrochemical method by optimizing potential fluctuations, and to estimate the environmental burdens for the electrochemical method using diluted hydrochloric acid and a chemical method using aqua regia.