Definition
High-Pressure Acid Leaching – A chemical process that dissolves nickel and cobalt out of low-grade laterite ore with sulfuric acid at high temperature and pressure, instead of smelting it. It is used to make intermediate products such as mixed hydroxide precipitate (MHP) that feed battery supply chains, and it needs very large up-front capital, a long ramp-up and a steady supply of sulfur and acid, so a project can take years to reach design output and its cost of capital weighs on returns. Found In: Project and segment disclosures (capital projects, investments in associates and joint ventures), and management commentary