Heavy metal recovery refers to the process of extracting valuable metals, such as gold, silver, and copper, from waste materials or contaminated environments. This process is essential for recycling resources and reducing environmental pollution caused by heavy metals, which can be toxic to living organisms. Techniques for heavy metal recovery include chemical precipitation, bioleaching, and electrochemical methods. These methods help to separate and concentrate metals from ores, industrial waste, or contaminated soil, making it possible to reuse these materials in various industries, thus promoting sustainability and resource conservation.