Nuclear Production of Hydrogen, Fourth Information Exchange ...

DEVELOPMENT OF CuCl-HCl ELECTROLYSIS FOR HYDROGEN PRODUCTION VIA Cu-Cl THERMOCHEMICAL CYCLE
Figure 1: Schematic diagram of the CuCl(aq)/HCl(aq) electrolytic system
Membranes
Ion exchange membrane (IEM) is a key component of the CuCl-HCl electrolytic system and is used to
separate the anodic and cathodic compartments as well as to provide ionic conductivity. For high
performance, the IEM needs to have high counter ion conductivity and selectivity as well as good
mechanical properties to withstand the aggressive concentrated HCl(aq) environment. To select the
best membrane for the CuCl-HCl electrolyser, a variety of commercial membranes were evaluated,
including anion exchange membranes (AEM) produced by Tokuyama Soda (AHA, AMX, ACS, ACM,
AM-3) and Asahi Glass (AHT), as well as Nafion, a proton exchange membrane produced by E.I. du Pont
de Nemours & Co., Inc. The membranes were characterised for swelling, ion exchange capacity (IEC),
and conductivity.
The membrane conductivity was measured in a specially designed “clip”-type conductivity cell
(Figure 2). The cell consists of two compartments with a membrane fixed in between. Two titanium
disk electrodes are applied to both sides of the membrane. Both compartments could be filled with
various solutions of a desired concentration.
Figure 2: Schematic of the conductivity cell
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