Higher: phytomining and bioleaching

The idea

The Earth's supply of high-grade copper ore is limited. Phytomining uses plants to absorb metal compounds from low-grade ores; the plants are harvested and burned, and the ash contains metal compounds. Bioleaching uses bacteria to produce leachate solutions containing metal compounds. Copper can then be obtained from these compounds by displacement using scrap iron or by electrolysis. These methods avoid digging, moving and disposing of large amounts of rock.

1. Describe phytomining step by step.
2. Describe bioleaching.
3. Explain how copper is obtained from the compounds.

Watch out These methods are slow, but useful for low-grade ores and waste.