Zhang Qian, a famous hydrometallurgical smelter in the Northern Song Dynasty of my country, was the first person in hydrometallurgy in the world. He once saw the record in the book that bile vitriol water can soak iron into copper, so he experimented. Bile water leaching of copper, that is, the use of copper sulfate solution to immerse iron to cause a chemical reaction to precipitate copper. The method can be called a major invention in the history of Chinese metallurgy and chemistry. Modern hydrometallurgy is a science and technology that uses leaching agent to dissolve valuable metals in ore and other materials in a solution to separate and extract metals. It occupies an important position in the industry. All alumina and uranium oxide in the world , Most zinc and part of copper are produced by wet methods. With the decline of ore grades and increasingly stringent requirements for environmental protection, hydrometallurgy plays an increasingly important role in the production of non-ferrous metals. The next issue will take you to understand powder metallurgy.