Table 10. Studies Related to Ammonia Decomposition in Membrane Reactors Reporting the Purity of Hydrogen Produced and Residual Ammonia Concentration in the Hydrogen Stream.
| Membrane |
Reactor
operating conditions |
Hydrogen
purity |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Author(s) [ref] | Selective layer composition | Selective layer thickness [μm] | Length [mm] | Temperature [°C] | Reaction pressure [bar] | Permeate pressure [bar] | NH3 feed flow rate [mLN/min] | GHSV [mL/(g–1cat h)] | Catalyst type | Maximum H2 purity [%] | NH3 concentration in the permeate [ppm] | Method used for NH3 concentration measurement |
| Zhang et al.17 | Pd | 6.2 | N/A | 450 | 5 | 1 | 100 | N/Aa | Cs (0.41 wt %) Ru/YSZ, Ru impregnated in the membrane support | >99.7 | <1000 | NDIR spectroscopy |
| Zhang et al.27 | Pd | ∼3 | N/A | 500 | 3 | 1 | 400 | 4000b | Ni/La-Al2O3 (Ni/Al = 1.20, La/Ni = 0.22), 6 g | >99.9a | N/A | N/A |
| Cechetto et al.40 | Pd-Ag | ∼6–8 | 195 | 500 | 2 | 1 | 500 | 120b | (2 wt %) Ru/Al2O3, 250 g | 99.998 | <0.75 | FTIR spectroscopy |
| Cechetto et al.65 | Pd-Ag | 4.61 | 202 | 450 | 1 | Vacuum | 500 | 120b | (2 wt %) Ru/Al2O3, 250 g | 99.995 | 2.91 | FTIR spectroscopy |
| Cerrillo et al.66 | Pd-Au | 8 | N/A | 350–500 | 4–15 | 1 | 100–310 | 600–1870b | (0.5 wt %) Ba-CoCe, 10 g | 99.97 ± 0.03 | N/A | Gas chromatography |
| Liu et al.67 | Pd/Pd-Ag | 6.5 | N/A | 400 | 3 | 1 | 47 | 1880b | (5 wt %) Ru/MgO, 1.5 g | 99.85a | N/A | N/A |
| Li et al.76 | SiO2 | <0.3 | N/A | 400 | 1 | Vacuum | 10 | N/A | (0.45 wt %) Ru/γ-Al2O3/α-Al2O3, Ru impregnated in the membrane support | 84.0 | 45,000 | Gas chromatography |
| Jiang et al.77 | MFI zeolite | 8 | N/A | 450 | 4.5 | 1 | 10 | 600 | (3 wt %) Ru/(1 wt %) Y/(12 wt %) K/Al2O3, 3 g | 91.16 | 3500 | Gas chromatography |
| CMSM | 0.9 | 220 | 450 | 7 | 1 | 250 | 5000 | 96.84 | <10,000 | Gas chromatography and NH3 sensor | ||
| Pd-Ag | 1.8 | 80 | 450 | 7 | 1 | 50–250b | 1000–5000 | >99.999 | <0.01 | |||
| Omata et al.83 | Pd-Ag/V-Fe | 0.2/100 | N/A | 350 | 3 | Vacuum | 10 | 3000b | (5 wt %) Ru/Cs2O/Pr6O11, 0.2 g | <99.9975 | <0.06 | Ion chromatography |
| Jo et al.84 | Pd/Ta | ∼0.4 μm Pd | N/A | 450 | 6.5 | 1 | 3000b | 30000 | (1.6 wt %) Ru/La-Al2O3, 6 g | >99.9999 | 0.8 | Tunable diode laser spectrometry |
| ∼250 μm Ta | ||||||||||||
| Park et al.85 | Pd/Ta/Pa | ∼1–2 | 76 | 425 | 3 | 1 | 20b | 1200 | (0.65 wt %) Ru/(10 mol %)La-Al2O3, 1 g | N/A | 4.2 | IR spectroscopy |
| Sitar et al.87 | Pd | 4.23 | 73 | 450 | 5 | 1 | 100–300 | 1200–3600b | (0.5 wt %) Ru/Al2O3, 5 g in the catalyst bed | N/A | 650a | Draeger tube |
| (1.9 wt %) Ru/YSZ (Ru impregnated in the membrane support) | ||||||||||||
a
Data not directly reported in the publication and retrieved from graphic representation of experimental results.
b
Data not directly reported in the publication. Calculated based on provided information about catalyst and flow rates used.