Product Code: 5041614
Fumasep FBM Bipolar Exchange Membrane with PKreinforcement consists of an anion exchange layer and a cation exchangelayer manufactured using a patented multilayer-coating productiontechnology. The polymer backbone for this bipolar membrane is based onhydrocarbon polymer materials.
This composite membrane is chemically stable andmechanically reinforced with woven PEEK. In the intermediate layer betweenAnion Exchange Layer (AEL) and Cation Exchange Layer (CEL), water isdissociated into OH- and H+ ions when exceeding a potential difference ofapproximately 0.8 V. The CEL must be directed towards the cathode, the AEL mustbe directed towards the anode, and the mode of operation has to be reversebiased in order to promote the water dissociation reaction. Under thereverse biased mode, the electrons would be transferred from anode side tocathode side. Water molecules would naturally diffuse into theintermediate layer between AEL and CEL and generation of H+ and OH- ions wouldoccur as a result of water splitting reaction. H+ ions will diffuse outfrom the CEL layer and migrate into the cathode chamber. OH- ions, on theother hand, would diffuse out from the AEL layer and migrate into the anodechamber.
The Fumasep FBM membrane should not be operated underforward bias conditions which may cause blistering at the water dissociationlayer. Under forward biasing conditions, water generation reaction will takeplace at the intermediate layer instead of water splitting reaction. H+ions will diffuse into the CEL and OH- will diffuse into the AEL during forwardbiased operational mode and combination of these two ions at the intermediatelayer will create water and hence, accumulation of water will happen overtime. Depending on the duration of the forward biasing mode and currentdensity or voltage, the water that accumulates at the center would eventuallydamage the bipolar membrane irreversibly. If the membrane is used in thewrong position at high current density even for short term (specificallyreferring to forward bias scenario), the interim layer may degrade (blisteringor ballooning), and the monolayers may delaminate. Depending on theoperational parameters of the forward biasing, micro-tears or micro-cracks thatare invisible to the naked eye may form and initiate the cross-contamination ofthe electrolytes located in different compartments.
The electro-catalytically forced water dissociationproduces in contrast to the classical electrolysis of water no reactiongases. Therefore, one Mol of OH- and H+ ions can be achieved at an energyvalue of approximately 22 Wh (Electrolysis: approximately 55 Wh per Mol).
Fumasep FBM membrane comes in a 20cm x 30cm size sheet isdelivered in wet form.
Fumatech membranes are highly sensitive to differences inhumidity and moisture content. Therefore the membranes can vary +/- 0.5cm fromthe original cut sizes. Also due to this sensitivity the manufacturer expectswrinkles to form, however soaking the membranes in deionized water will returnthe membranes to the full size planar state according to the manufacturer.
Fumasep FBMmembrane is Easy to Use and Show:
High water splitting efficiency (> 98% at 100 mAcm-2 in 0.5 M NaCl at 25C)
Low water splitting voltage (< 1.2 V at 100 mA cm-2 in 0.5 M NaCl at 25C)
Excellent mechanical properties at low thickness (0.13 0.16 mm)
Application: Salt Splitting
Bipolar Exchange Membrane
Stability range (pH) at 25 C: 1 - 14
Can withstand high caustic concentrations
Thickness: 200 - 250 micrometers (7.8 - 9.8 mil)
Size: 20cm x 30cm
Please pay attention that the membrane surface is notcontaminated with surface active agents or will be damaged by mechanicalinfluence.
High attention must be given to the right polarity whenusing the membranes!
When mounting the membranes it is imperative that themembrane sides will not get mixed up. Therefore, the cation side is markedwith Cathode Side. This side must be directed towards the cathode (seealso drawing overleaf).
The membrane should be stored in 1 M NaCl-solution andplaced in a closed container. If storage will be for a longer period of time100 ppm of NaN3 should be added to prevent biological growth. Other biocideshave not been used as yet.
The membrane is not stable against chlorine (Cl2).
If you have any concerns before proceeding, please feelfree to contact us for further information.
Current Voltage Characteristics of Fumasep FBM:
4-chamberset-up: cathode Na2SO4 CEM NaCl FBM NaCl CEM Na2SO4 solution anode
4-probe measurement: Haber-Luggincapillary (3 M KCl) with Ag / AgCl reference electrodes
CEM: Cation exchange membrane FKB
Electrolyte loop: 0.5 M NaCl solution /recombined
Electrode loop: 0.25 M Na2SO4 /recombined
Fixed scan rate, U = 20 mV, t =20s.