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A simple method of improving hydrogen generation from the reaction between highly activated Mg powder and water is established. The Mg–H2O reaction is found to become faster and more intense when magnesium is mixed with salts and subjected to by high-energy ball milling. Among the studied salts, AlCl3 has the best performance. The milling time and salt content significantly affect the final hydrogen yield and reaction kinetics. Among all studied samples, 6 h-milled Mg–3 mol% AlCl3 shows the best performance with a hydrogen yield of 93.86% and IHGR (initial hydrogen generation rate) of 455.9 ml min−1·(g Mg)−1 within 1 h. The initial temperature is also found to have a remarkable influence on the hydrolysis of the Mg–AlCl3 mixture, and the reaction can proceed to 100% conversion in 1 min with an IHGR of 933.3 ml min−1·(g Mg)−1 at 80 °C. [ABSTRACT FROM AUTHOR]

Abstract: On-site on-demand hydrogen generation from a new Mg–LiBH4–AlCl3 system has been established. The hydrogen yield, mHGR (maximum hydrogen generation rate) and reaction stability can be adjusted by changing the samples' compositions, milling time and water/mixture ratios. The Mg-9 wt.%LiBH4-1 wt.%AlCl3 composite reaches a conversion yield of 87%, corresponding to 1083.5 ml H2 g−1 (composite), and the mHGR is 1256.9 ml min−1 g−1 in 60 min at 298 K. The synergistic effect between Mg and LiBH4 as well as the catalytic effects of LiBH4–AlCl3 additives both contribute to the improved hydrolytic performances. Compared with the hydrolysis of single Mg or Mg–LiBH4 system, the Mg–LiBH4–AlCl3 mixture has greatly improved its hydrogen yield and mHGR. This mixture is promising for its application as portable hydrogen sources. [Copyright &y& Elsevier]