Bauxite can dump lead and arsenic into waterways, and the process of refining bauxite into aluminum is expensive and energy-intensive. The obvious answer is recycling, which avoids dirty mining and uses only 5% of the energy used to produce new aluminum. But aluminum recycling can be tricky. Aluminum reacts easily with oxygen in the air, rendering it useless as a metal. Chemists are interested in recycling aluminum not to create new metals, but to create aluminum-based catalysts. That has its own problems. Some attempts over the years have proven to be too expensive, too energy-intensive, or have produced harmful by-products.
