Improvement in Hydrogention and Dehydrogenation Characteristics of Magnesium by Addition of Titanium (III) Chloride via Transformation-Accompanying Milling

  • Myoung Youp SONG
  • Seong Ho LEE
  • Young Jun KWAK
  • Hye Ryoung PARK
Keywords: hydrogen storage, magnesium-based alloys, transformation-accompanying milling, hydrogen sorption rates

Abstract

A specimen consisting of 90 wt.% Mg and 10 wt.% TiCl3 (called 95 Mg + 10 TiCl3) was made by transformation-accompanying milling, and its hydrogenation and dehydrogenation features were checked. The activation of 95 Mg + 10 TiCl3 was not demanded. 95 Mg + 10 TiCl3 revealed an useful hydrogenation-dehydrogenation capacity (the quantity of hydrogen absorbed in 60 min) of about 5.6 wt.%. At n = 1, the specimen absorbed 4.06 wt.% of hydrogen in 5 min, 5.09 wt.% of hydrogen in 10 min, and 5.59 wt.% of hydrogen in 60 min at 593 K in 1.2 MPa H2. At n = 1, the specimen desorbed 0.47 wt.% of hydrogen in 2.5 min, 3.81 wt.% of hydrogen in 30 min, and 5.20 wt.% of hydrogen in 60 min at 593 K in 0.1 MPa H2. The XRD pattern of 95 Mg + 10TiCl3 dehydrogenated at the 4th hydrogenation-dehydrogenation cycle included Mg, β-MgH2, MgO, and a small amount of TiH1.924 phases. The P (equilibrium hydrogen pressure)-C (composition)-T (temperature) curve at 593 K revealed an equilibrium plateau pressure at about 0.25 MPa. 95 Mg + 10 TiCl3 had a higher early hydrogenation rate and a larger amount of hydrogen absorbed in 60 min than Mg, 90 Mg + 10 Fe2O3, 90 Mg + 10 MnO, and 90 Mg + 10 TaF5, the hydrogenation and dehydrogenation features of which were before informed of.

DOI: http://dx.doi.org/10.5755/j01.ms.23.3.16375

Published
2017-04-21
Section
METALS, ALLOYS, COATINGS