Resumo (PT):
Abstract (EN):
This work investigates the influence of carbon dioxide and non-reacted methanol, present
in the reformate stream obtained via methanol steam reforming, in the performance of
high temperature polymer electrolyte membrane fuel cells (HT-PEMFC), operating between
160 C and 180 C.
The HT-PEMFC anode was fed with pure hydrogen, hydrogen balanced with carbon
dioxide (75%/25% vol.) and synthetic reformate mixture, considering also vaporized
methanol solution in the reformate content (up to 10% vol.). The synthetic reformate was
feed during cycles of 420 min. The fuel cell was characterized based on the polarization
curve and electrochemical impedance spectroscopy (EIS) analysis. Additionally, acidebase
titrations were performed to access the phosphoric acid content in different sections of the
MEAs as well as scanning electron microscopy (SEM).
A low impact in the fuel cell performance was observed when three cycles of synthetic
reformate containing methanol solution were performed. When the number of cycles was
increased, the performance of HT-PEMFC decreases and irreversible degradation of performance was observed. The cycles with synthetic reformate increased the ohmic resistance and high frequency resistance associated with anodic processes, but decreased the
intermediate frequency resistance associated with cathodic processes. Additionally, by
increasing the number of cycles, the phosphoric acid content of Celtec® MEAs and the
thickness of the membrane decreased.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica
Notas:
Journal Citation Reports
Nº de páginas:
10