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In this study, a novel process was developed to produce Al/AlN composites by infiltrating molten Al ingot into a mixture of Al and lamp carbon powders. The findings revealed that, during the process, Al2O3 on the surface of Al powder reacted with nitrogen gas and was transformed to AlN. The degree of nitridation was greatly enhanced by adding only less than 3 wt.% lamp carbon, because lamp carbon could act as a dispersion agent as well as a reduction agent. The Al-based composites containing in situ AlN phases showed coefficient of thermal expansion values of ∼11 × 10−6/℃, which were comparable to those of composites containing 60% ex situ AlN particles.

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Recently, many studies have been conducted on the materialization of spent batteries. In conventional cases, lithium is recovered from an acidic solution through the leaching and separation of valuable metals; however, it is difficult to remove impurities because lithium is recovered in the last step. Cathode active materials of lithium-ion batteries comprise oxides with lithium, such as LiNixCoyMnzO2 and LiCoO2. Thus, lithium should be converted into a compound that can be leached in deionized water for selective lithium leaching. Recent studies on the leaching and recovery of Li2CO3 through a carbon reduction reaction show low economic efficiency, due to the solubility of Li2CO3 at room temperature being as low as 13 g/L. This paper proposes a method of roasting after nitric acid deposition for selective lithium leaching and recovery to LiNO3. Based on experiments involving the varying of the amount of nitric acid, roasting temperature, and solid–liquid ratio, optimal values were found to be dipping in 10 M HNO3 2 mL/g, roasting at 275 °C, and deionized water with a solid–liquid ratio of 10 mL/g, respectively. Over 80% Li leaching was possible under these conditions. IC analysis confirmed that the purity was 97% lithium nitrate.