Nafion membranes come in many different thickness and types. How do you know which to choose when designing an electrolyzer.
Choosing the proper thickness depends primarily on the differential pressure you expect across the membrane (i.e. what pressure you will be generating the hydrogen at vs. the oxygen), the type of support the membrane will have, and the operating lifetime (both hours and on/off cycles).
When would you use a thinner membrane?
When the best efficiency is required and there won’t be much differential pressure across the membrane. We have made membranes using Nafion 212(0.002″ thick), Nafion 211 (0.001″); chemically reinforced) that have all been shown to be exceptionally efficient.
What about thicker membranes?
Thicker membranes and fiber reinforced membranes are more appropriate for very high differential pressure applications (1000+ psi) or very long operating life (100,000+ hrs).
You can download chart Here
Nafion Membrane Comparison Chart | |||||||
Properties of NafionTM PFSA Membranes | |||||||
Membrane Type |
Nafion NRE-211 | Nafion NRE-212 | Nafion NE 1035 | Nafion 115 | Nafion 117 | Nafion 1110 | |
Thickness, Micrometer (mil) | 25.4 (1) | 50.8 (2) | 89 (3.5) | 125 (5) | 183 (7) | 254 (10) | |
Basis Weight, g/m² | 50 | 100 | 175 | 250 | 360 | 500 | |
Tensile Modulus, MPa (kpsi)** | 249 (36) | 249 (36) | 249 (36) | ||||
Tensile Strength, maximum, MPa (kpsi)** | MD | 23 (3.3) | 32 (4.6) | 43 (6.2) | 43 (6.2) | 43 (6.2) | |
TD | 28 (4.1) | 32 (4.6) | 32 (4.6) | 32 (4.6) | 32 (4.6) | ||
Elongation at Break, %** | MD | 252 | 343 | 225 | 225 | 225 | |
TD | 311 | 352 | 369 | 310 | 310 | 310 | |
Tear Resistance – Initial, g/mm** | MD | 6000 | 6000 | 6000 | |||
TD | 6000 | 6000 | 6000 | ||||
Tear Resistance – Propagating, g/mm** | MD | >100 | >100 | >100 | |||
TD | >150 | >150 | >150 | ||||
Specific Gravity | 1.97 | 1.97 | 2 | 1.98 | 1.98 | 1.98 | |
Available Acid Capacity, meq/g | 0.92 min | 0.92 min | 1.0 min | 0.90 min | 0.90 min | 0.90 min | |
Total Acid Capacity, meq/g | 0.95 to 1.01 | 0.95 to 1.01 | 1.03 to 1.12 | 0.95 to 1.01 | 0.95 to 1.01 | 0.95 to 1.01 | |
Water Content, % Water | 5.0 ± 3.0% | 5.0 ± 3.0% | 5% | 5 | 5 | 5 | |
Water Uptake, % Water | 50.0 ± 5.0% | 50.0 ± 5.0% | 43% | 38 | 38 | 38 | |
Thickness % Increase (from 50% RH, 23 °C to water soaked, 23 °C) | 10% | 10% | 10% | ||||
Thickness % Increase (from 50% RH, 23 °C to water soaked, 100 °C) | 14% | 14% | 14% | ||||
Linear Expansion, % Increase (from 50% RH, 23 °C to water soaked, 23 °C) | 10% | 10% | 10% | 10% | 10% | 10% | |
Linear Expansion, % Increase (from 50% RH, 23 °C to water soaked, 100 °C) | 15% | 15% | 15% | 15% | 15% | 15% |