Bioprocessing of Metals from Packaging Wastes

Packaging refers to the covering used to protect the product inside. Metals—such as iron, copper, and their alloys, i.e., brass and bronze, have been used for the packaging and storage of goods since ancient times. Unique properties of metals, particularly the ease of fabrication, strength, thermal and electrical conductivities, and ability to hold diverse materials securely in different states, make them an essential packaging material either as such or as composites with materials such as polymers, fibers, plastics, and ceramics. Boxes, cans, cylinders, and foils made from iron, aluminum, tin, copper, etc., are the most common and everyday examples of metal-based packaging; however, specialized packaging requirements, e.g., for electronic parts, composites based on different metals are preferred. After its end use, discarded packaging becomes a major contributor to waste generation. Completely metal-based packages can be recycled; however, this becomes expensive for composites. In such cases, landfilling is the most common disposal method, which may cause adverse impacts on human health through the contamination of groundwater and soil. This calls for effective and better alternate metal waste-management options that can help metal recycling and recovery. In this chapter, we present a brief introduction of metal-based packaging, their various methods of disposal, and recovery and recycling options with particular focus on biotechnological approaches. With the help of different examples and recent developments in the recovery and reuse of waste metals, potential sustainable and cost-effective solutions in managing metallic or metal-based packaging waste are discussed.