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Hydrometallurgy is a technique within the field of extractive metallurgy, the obtaining of metals from their ores.Hydrometallurgy involve the use of aqueous solutions for the recovery of metals from ores, concentrates, and recycled or residual materials.
The ocean plays a key role in the water cycle as it is the source of 86% of global evaporation. [2] The water cycle involves the exchange of energy, which leads to temperature changes. When water evaporates, it takes up energy from its surroundings and cools the environment. When it condenses, it releases energy and warms the environment.
In metallurgy, refining consists of purifying an impure metal. It is to be distinguished from other processes such as smelting and calcining in that those two involve a chemical change to the raw material, whereas in refining the final material is chemically identical to the raw material. Refining thus increases the purity of the raw material ...
The study of sintering in metallurgical powder-related processes is known as powder metallurgy. An example of sintering can be observed when ice cubes in a glass of water adhere to each other, which is driven by the temperature difference between the water and the ice.
Another key step in the Wacker process is the migration of the hydrogen from oxygen to chloride and formation of the C-O double bond. This step is generally thought to proceed through a so-called β-hydride elimination with a cyclic four-membered transition state: Wacker hydride elimination
The copper cycle is the biogeochemical cycle of natural and anthropogenic exchanges of copper between reservoirs in the hydrosphere, atmosphere, biosphere, and lithosphere. Human mining and extraction activities have exerted large influence on the copper cycle.
The Cu–Cl cycle is a hybrid process that employs both thermochemical and electrolysis steps. It has a maximum temperature requirement of about 530 degrees Celsius. [1] The Cu–Cl cycle involves four chemical reactions for water splitting, whose net reaction decomposes water into hydrogen and oxygen. All other chemicals are recycled.
Metallurgy derives from the Ancient Greek μεταλλουργός, metallourgós, "worker in metal", from μέταλλον, métallon, "mine, metal" + ἔργον, érgon, "work" The word was originally an alchemist's term for the extraction of metals from minerals, the ending -urgy signifying a process, especially manufacturing: it was discussed in this sense in the 1797 Encyclopædia ...