One of the ideal energy carriers for the future is hydrogen. It has a high energy density and is a source of clean energy. A crucial step in the development of the hydrogen economy is the safety and affordable storage of a large amount of hydrogen. Thus, owing to its large storage capacity, good reversibility, and low cost, Magnesium hydride (MgH₂) was taken into consideration. Unfortunately, MgH₂ has a high desorption temperature and slow ab/desorption kinetics. Using the ball milling technique, adding cobalt lanthanum oxide (LaCoO₃) to MgH₂ improves its hydrogen storage performance. The results show that adding 10 wt.% LaCoO₃ relatively lowers the starting hydrogen release, compared with pure MgH₂ and milled MgH₂. On the other hand, faster ab/desorption after the introduction of 10 wt.% LaCoO₃ could be observed when compared with milled MgH₂ under the same circumstances. Besides this, the apparent activation energy for MgH₂–10 wt.% LaCoO₃ was greatly reduced when compared with that of milled MgH₂. From the X-ray diffraction analysis, it could be shown that in-situ forms of MgO, CoO, and La₂O_3, produced from the reactions between MgH₂ and LaCoO₃, play a vital role in enhancing the properties of hydrogen storage of MgH₂.

This study explores the possible use of ionic liquids as a solvent in a commercial high-pressure CO₂ removal process, to gain environmental and energy benefits. There are two main constraints in realizing this: ionic liquids can be corrosive, specifically when mixed with a water/amine solution with dissolved O₂ & CO₂; and CO₂ absorption within this process is not very well understood. Therefore, scavenging CO₂ to ppm levels from process gas comes with several risks. We used 1-butyl-3-methylimidazoium methane sulphonate [bmim][MS] as an ionic liquid because of its high corrosiveness (due to its acidic nature) to estimate the ranges of expected corrosion in the process. TAFEL technique was used to determine these rates. Further, the process was simulated based on the conventional absorption–desorption process using ASPEN HYSYS v 8.6. After preliminary model validation with the amine solution, [bmim][MS] was modeled based on the properties found in the literature. The energy comparison was then provided and the optimum ratio of the ionic liquid/amine solution was calculated.

The high hydrogen storage capacity (10.5 wt.%) and release of hydrogen at a moderate temperature make LiAlH₄ an appealing material for hydrogen storage. However, LiAlH₄ suffers from slow kinetics and irreversibility. Hence, LaCoO₃ was selected as an additive to defeat the slow kinetics problems of LiAlH₄. For the irreversibility part, it still required high pressure to absorb hydrogen. Thus, this study focused on the reduction of the onset desorption temperature and the quickening of the desorption kinetics of LiAlH₄. Here, we report the different weight percentages of LaCoO₃ mixed with LiAlH₄ using the ball-milling method. Interestingly, the addition of 10 wt.% of LaCoO₃ resulted in a decrease in the desorption temperature to 70 °C for the first stage and 156 °C for the second stage. In addition, at 90 °C, LiAlH₄ + 10 wt.% LaCoO₃ can desorb 3.37 wt.% of H₂ in 80 min, which is 10 times faster than the unsubstituted samples. The activation energies values for this composite are greatly reduced to 71 kJ/mol for the first stages and 95 kJ/mol for the second stages compared to milled LiAlH₄ (107 kJ/mol and 120 kJ/mol for the first two stages, respectively). The enhancement of hydrogen desorption kinetics of LiAlH₄ is attributed to the in situ formation of AlCo and La or La-containing species in the presence of LaCoO₃, which resulted in a reduction of the onset desorption temperature and activation energies of LiAlH₄.