Due to the climate change and other environmental aspects linked to the use of fossil fuels, renewable energy and clean technologies such as hydrogen/oxygen fuel cells have gained renewed interest in the last decades. However, fuel cell manufacture and management of spent fuel cells could also represent a significant impact on the environment. Several studies to assess the extent of this impact were carried out using life cycle analysis (LCA) [1-6], concluding that the membrane electrode assembly (MEA) is the component that contributes the most to the overall environmental impact, mainly due to the extraction of platinum group metals (PGM), which are the main contributor to the acidification burden of MEA manufacture. These studies also affirm that important reductions in pollution can be achieved if the MEA materials are recycled. The recovery of the PGM can be achieved through thermal, chemical or biological methods [7,8]. All of these methods present benefits and drawbacks. For example, thermal treatments are not an environmentally friendly option when recycling most commonly used MEAs, since the Nafion membrane generates acids in the combustion. On the other hand, although biological recovery of PGM is the most environmentally preferable process, there is lack of studies on the integration of this step with the MEA recycling process. The recovery of PGM or membrane materials from MEAs using chemical methods is well documented. Nonetheless, very few studies seem to propose a method to recover both the catalyst and the membrane at the same time, even though the membrane material highly contributes to the final MEA cost.

This work proposes a new recycling method of MEAs from hydrogen-oxygen fuel cells, where all main components like the Nafion membrane, carbon powder and metallic platinum were recovered through chemical methods.

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