A leaching process for the recovery of cobalt and lithium from spent lithium ion batteries (LIB) is developed in this work. Three different organic acids, namely citric acid, malic acid and aspartic acid, are used as leaching reagents in the presence of hydrogen peroxide.
Depending on the desired metal, and its original matrix, different solvents can be used in the leaching process, these solvents are known as lixiviants. For those of you unfamiliar to the term, lixiviate means to leach, or dissolve out.
Leaching can be followed by conventional metal recovery methods like solvent extraction, precipitation, adsorption, ion exchange and electrowinning.
Different leaching processes and the leaching of metals from various metal bearing solid wastes are discussed in detail below. 6.3.1 Hydrometallurgical Processes Hydrometallurgy is the extraction of metals from resources with the help of aqueous chemicals.
This BREF document covers fourteen different metals, including gold, that are mined and/or processed in the European Union (EU 15), the acceding countries, the candidate countries and Turkey, Heap leaching techniques are briefly addressed in this version of the BREF document but not sufficiently described.
Some metals like gold and silver are extracted from their concentrated ores by leaching. They are dissolved in suitable reagents like acids or bases leaving behind insoluble impurities. The metal is recovered from the solution by displacement with some more electropositive metal such as zinc.
In other words, metals bound in minerals are transformed into metal ions that are released into an aqueous solution, i.e. immobilized metals become mobilized. Extraction of metals from ores to aqueous solutions by means of chemicals. Leaching occurs naturally but may also be applied as a preparatory step for metal recovery.
metals could be recovered from these ashes. This can be done through chemical leaching; researchers have determined that leaching of ashes should be carried out in acid solutions. It has been shown that metals leach most efficient at lower pH value but for some metals the release rate of metals are still as efficient at higher pH value.
high grade primary metal resources, which urges the metal producing industries to look for secondary alternative sources for metal extraction (Anjum et al. 2012). Metal bearing wastes from different industries can be such alternative resources for the recovery of metals, as some of the wastes still contain signicant levels of valuable metals.
Leaching platinum group metals with cyanide, however, is a new concept and process option. The research available is very much limited to the recovery of platinum group metals from recycled automotive catalyst using cyanide 8 14 .
These metals can be recovered from E waste at cheaper cost than from the usual ores. Techniques like pyrometallurgy, hydrometallurgy, and biohydrometallurgy are used to recover precious metals like copper, silver and gold.
different types of materials, especially lean and so far unusable resources, by which metal values can be recovered. Lastly, the process is carried out in close loop generating minimum effluents and thus is preferred as green technology.