Leaching (chemistry)

There are many types of leaching scenarios; therefore, the extent of this topic is vast. At the beginning of the leaching process, substance C will work at dissolving the surficial substance B at a fairly high rate. A major concern for leaching of plants, is if pesticides are leached and carried through stormwater runoff,; The Tennessee Valley Authority Kingston Fossil Plant structural failure lead to massive destruction throughout the area and serious levels of contamination downstream to both Emory River and Clinch River. In recent years, there has been more attention given to metal leaching to recover precious metals from waste materials. For example, the extraction of valuable metals from wastewater. == Leaching mechanisms ==

Due to the assortment of leaching processes there are many variations in the data to be collected through laboratory methods and modeling, making it hard to interpret the data itself. Not only is the specified leaching process important, but also the focus of the experimentation itself. For instance, the focus could be directed toward mechanisms causing leaching, mineralogy as a group or individually, or the solvent that causes leaching. Most tests are done by evaluating mass loss due to a reagent, heat, or simply washing with water. A summary of various leaching processes and their respective laboratory tests can be viewed in the following table: ==Environmentally friendly leaching==

Some recent work has been done to see if organic acids can be used to leach lithium and cobalt from spent batteries with some success. Experiments performed with varying temperatures and concentrations of malic acid show that the optimal conditions are 2.0 m/L of organic acid at a temperature of 90 °C. The reaction had an overall efficiency exceeding 90% with no harmful byproducts. :4 LiCoO2(solid) + 12 C4H6O5(liquid) → 4 LiC4H5O5(liquid) + 4 Co(C4H6O5)2(liquid) + 6 H2O(liquid) + O2(gas) The same analysis with citric acid showed similar results with an optimal temperature and concentration of 90 °C and 1.5 molar solution of citric acid. ==See also==