Gamry Instruments MultiPort, Руководство оператора

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Chemical Compatibility of the MultiPort Cell Kit--Checking for Shipping Damage
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Chemical Compatibility of the MultiPort Cell Kit
The components in the MultiPort Cell Kit were selected to be as chemically inert as possible. In normal use, the
only materials in contact with the test solution are:
•
The corrosion sample
•
Borosilicate glass (Pyrex ® or equivalent)
•
Unfired glass frit
•
PTFE
•
Polyethylene
•
Ace Glass’s FETFE O -ring material
Chemical resistance tables for most of these materials are available (try searching the Internet). One exception is
FETFE, which is a elastomer proprietary to Ace Glass, which consists of PTFE particles in a fluorinated rubber
base similar to Viton
® . According to Ace Glass, it offers slightly better chemical resistance than Viton ® .
The black ACE- Thred™ fittings supplied with the cell do not normally come in contact with the cell electrolyte.
These are nylon fittings, so you can use nylon’s properties (which are generally available) as an indication of
these fitting’s suitability for use in any specific chemical environment.
Gamry’s MultiPort was not designed for use in electrolytes that dissolve glass (extremely basic solutions or HF-
containing solutions).
The simple construction of the polyethylene stoppers used to seal the unused port makes them easily adaptable
as a vent for purge gas: you simply poke a hole in the flat surface of the stopper. While they provide chemical
resistance to most aqueous electrolytes, they may not be a good choice for use with some aggressive solvents. If
polyethylene is not suitable for your application, glass and PTFE stoppers are available from most laboratory
supply houses.
If you use these “more solid” stoppers, do not forget the need to vent purge gas from the cell.
Caution:
The glass components in the cell and the glass frits used in the reference bridge
tube are not suitable for use with extremely basic solutions or solutions containing hydrofluoric acid. We do
not know of any substitute cell components that will completely overcome this limitation. If you need to
work with solutions that will damage the cell, we recommend that you design and build an all-plastic cell.
Caution:
The nylon bushings in the ACE- Thred™ fittings and the FETFE O -rings may not be
suitable for use in some electrolytes (particularly non-aqueous media). If you need better chemical
resistance than that offered using the standard ACE-Thred components, ACE Glass (www.aceglass.com) can
provide replacement fittings made from PTFE and Kalrez
® , which are extremely resistant to chemical attack.
Contact Gamry Instruments, if you need help selecting the proper replacement fittings.