A Life Cycle Assessment of the PureCell Stationary Fuel Cell System ...

manufacturing phase and a high negative environmental impact in the end-of-life phase
because of platinum recycling. It does however not represent the platinum cycle for the
PureCell system correctly. UTC Power aims to recollect the CSA’s and extract the
platinum for reuse, resulting in a UTC Power internal recycling process. A schematic of
this ‘internal lease’ cycle is shown in Figure 4-3.
Figure 4-3: UTC Power platinum internal recycling
Thus, 2% of the platinum input into the CSA manufacturing process was raw platinum
and 98% was recycled. Recycled platinum was modeled in SimaPro with LCI data from
[13].
Teflon®
LCI data for the production of Teflon® could not be found. Polyethylene (PE granulate
average B250 PureCell system) was used in the LCA model instead. An investigation
by the United States EPA is running regarding the chemical PFOA (perfluorooctanoic
acid) [14], which is both used and emitted in the production process of Teflon®. PFOA
is very persistent in the environment, and is shown to cause developmental and other
adverse effects in laboratory animals. Recognizing the fact that a significant amount of
Teflon® is used (467.7 lb), one must realize that substituting Teflon® with polyethylene
probably leads to an underestimation of the modeled environmental impact of Teflon®.
Graphite
LCI data for modeling the graphite production process was obtained by EIO-LCA
(Economic Input-Output LCA) [15] because no process for graphite was included in the
SimaPro databases and no other literature containing LCI data on graphite production
could be found. With this method LCI data are calculated based on a product category
and the cost in dollar value to make the output. For graphite, the category ‘Carbon and
graphite product manufacturing’ was selected with a product value of $6,924 (UTC
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