Kirk, Jaewon Kim, Yoondo Lee, Yu-Jin Kim, Minkyu Min, Dong-Su Kim, Pyung Soon Seo, Ji Hui Kim, Yongwoo Lee, Jaeyong Choung, Jin Woo Sohn, Hyuntae Nam, Suk-Woo Yoon, Chang-Won Kim, Yongmin Jeong, Hyangsoo 2024-01-19T09:30:50Z 2024-01-19T09:30:50Z 2023-07-13 2023-06 1385-8947 https://pubs.kist.re.kr/handle/201004/113647 Sodium borohydride (SBH) is a promising hydrogen (H2) carrier; however, its successful deployment has been limited to unmanned aerial vehicle applications. We reevaluated SBH hydrolysis for on-board vehicular appli-cations from an entirely new perspective using solid-phase SBH hydrolysis with a CO2-derived acid at elevated temperatures and pressures, enabling extremely efficient water utilization. This strategy afforded a high H2 storage density of 6.33 wt%, which could be extended to 10.4 wt% via water recovery from fuel cells. High -purity H2 with carbon monoxide levels below 10 ppm was obtained after methanation. Importantly, an energy-efficient SBH regeneration method using residual NaHCO2 was developed. A 1.2-kWe-level SBH hydrogen generation was evaluated with the fuel-cell operation, and a 20-kWe-level compact system was developed with a system-based volumetric H2 storage density of 25 g-H2/L. This technology will accelerate SBH-based vehicular applications at a level of 50 g-H2/L. English Elsevier BV Pushing the limits of sodium borohydride hydrolysis for on-board hydrogen generation systems Article 10.1016/j.cej.2023.143233 1 Chemical Engineering Journal, v.466 Chemical Engineering Journal 466 N scie scopus 001006896100001 2-s2.0-85158915156 Engineering, Environmental Engineering, Chemical Engineering Article FORMIC-ACID GAS DEHYDROGENATION FUNDAMENTALS METABORATE CATALYST VEHICLE DESIGN WATER NABH4 Hydrogen production Sodium borohydride Formic acid 20kW e -level H 2 generation system Borax regeneration Sodium borohydride value chain