Among the sea-water specific impurities tested, magnesium has the most profound effect on PEM-cell degradation. Significant amounts of the cation was retrieved in the NAFION®-membrane structure after testing. Degradation was seen from a magnesium concentration as low as 3 10-7 mol/l, and increasing with concentration it led to a 86% increase of the area specific resistance at a concentration of 3 10-5 mol/l; equivalent to a conductivity of ~5 μS/cm. Other species (Cl-, Na+, SO4 2- ) seems to affect, though slowly, the performance negatively. If PEM will be used for electrolysis it seems therefore necessary to purify the feed water to ~1 μS/cm or even further while particularly focusing on the concentrations of polyvalent cations. e.g. magnesium.
|Number of pages||1|
|Publication status||Published - 2014|
|Event||2nd Euro-Mediterranean Hydrogen Technologies Conference - Taormina, Italy|
Duration: 9 Dec 2014 → 12 Dec 2014
|Conference||2nd Euro-Mediterranean Hydrogen Technologies Conference|
|Period||09/12/2014 → 12/12/2014|