Hydrogen Valorization from Industrial Waste Streams Using Matrimid/LaNi₅ Mixed Matrix Hollow Fiber Membranes

Area of Science:

• Materials Science
• Chemical Engineering
• Separation Technology

Background:

• Industrial residual gas streams present opportunities for hydrogen recovery to improve efficiency and reduce environmental impact.
• Polymeric membranes are crucial for hydrogen recovery, but their performance is limited by the selectivity-permeability trade-off.
• Scalable membrane solutions are needed for practical industrial application.

Purpose of the Study:

• To enhance hydrogen recovery from industrial residual gas streams using novel mixed matrix hollow fiber membranes.
• To improve the selectivity-permeability performance of polymeric membranes through the incorporation of hydrogen storage intermetallic compounds.
• To evaluate the performance and stability of these membranes under industrially relevant conditions.

Main Methods:

• Incorporation of LaNi₅ (a hydrogen storage intermetallic compound) into a polyimide matrix to create mixed matrix hollow fiber membranes.
• Gas permeation experiments were conducted to evaluate membrane performance for hydrogen recovery.
• SEM-EDX analysis was used to confirm the uniform distribution of LaNi₅ fillers.
• Mathematical modeling was employed to analyze hydrogen permeation through the hollow fiber membranes.

Main Results:

• Membranes with 5 wt% LaNi₅ exhibited 2.5 times higher H₂ permeance (38.4 GPU) compared to pristine Matrimid fibers.
• Enhanced selectivity was achieved: 6.2 for H₂/CO₂ and nearly 65 for H₂/N₂, H₂/CH₄, and H₂/CO.
• The membranes demonstrated stable performance for approximately 580 hours of continuous operation.
• A hydrogen permeation model accurately predicted experimental data within a ±15% threshold.

Conclusions:

• The developed LaNi₅-based mixed matrix hollow fiber membranes offer high performance for hydrogen recovery from industrial waste gas streams.
• The incorporation of LaNi₅ significantly improves both hydrogen permeance and selectivity.
• The hollow fiber configuration and stable performance support the scalability and practical application of these membranes in industrial processes.