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Updated: Jul 2, 2025
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A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
Published on: August 17, 2016
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A novel micro-reactor for hydrogen production from solid NaBH4 hydrolysis in a dual-cycle methodology
Eyal Hayouk1, Alex Schechter2, Idit Avrahami1
1Department of Mechanical Engineering & Mechatronics, Ariel University, Ariel, 40700, Israel.
Heliyon
|February 26, 2024
Summary
A new dual-cycle generator (DCG) enhances hydrogen production from sodium borohydride (NaBH4) and water. This system overcomes saturation issues, boosting energy density and operational duration for fuel cells.
Area of Science:
- Energy conversion technologies
- Chemical engineering
- Materials science
Background:
- Hydrogen-based Fuel Cells (FCs) offer significant potential for energy conversion.
- Previous pump-based hydrogen generators (PHG) using sodium borohydride (NaBH4) showed safety and energy density advantages.
- PHG systems face limitations due to solution saturation over extended operation, reducing reaction rates.
Purpose of the Study:
- To introduce and evaluate a novel dual-cycle generator (DCG) for hydrogen production.
- To overcome the solution saturation limitation in NaBH4-based hydrogen generation.
- To enhance energy density and operational duration for mobile and off-grid applications.
Main Methods:
- Development and testing of a dual-cycle generator (DCG) prototype.
- Integration of solution circulation with freshwater feeding and product emission.
- Examination of various operating modes to assess system performance.
Main Results:
- The DCG achieved a fuel energy density of 3868 Wh/kg.
- A 93% H2 extraction yield from sodium borohydride powder was obtained.
- Substantial improvements were observed: 81% extended operation duration, 36% increased hydrogen flow rate, 33% enhanced energy density, and 39% improved H2 yield.
Conclusions:
- The dual-cycle generator (DCG) effectively overcomes solution saturation in hydrogen production.
- This innovative approach significantly enhances hydrogen fuel's energy density and operational time.
- The DCG technology shows promise for mobile applications and off-grid systems near water sources.
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