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In manufacturing, the simulated moving bed (SMB) process is a highly engineered process for implementing chromatographic separation. It is used to separate one chemical compound or one class of chemical compounds from one or more other chemical compounds to provide significant quantities of the purified or enriched material at a lower cost than could be obtained using simple (batch ...
Sodium metabisulfite, despite not being flammable, decomposes in 150 °C of heat releasing toxic gasses when decomposed. It is corrosive when dissolved in water. Some people who are sulfite sensitive may experience an allergic reaction to sodium meta bisulfite, sometimes severe, resulting in labeling requirements for food safety. [20]
Salting out (also known as salt-induced precipitation, salt fractionation, anti-solvent crystallization, precipitation crystallization, or drowning out) [1] is a purification technique that utilizes the reduced solubility of certain molecules in a solution of very high ionic strength.
Potassium metabisulfite is sometimes used to precipitate gold from solution in aqua regia (as an alternative to sodium sulfite). It is a component of certain photographic developers and solutions used in photographic processing, keeping active developing species from contact with oxygen.
The gold atom centers in Au(III) complexes, like other d 8 compounds, are typically square planar, with chemical bonds that have both covalent and ionic character. Gold(I,III) chloride is also known, an example of a mixed-valence complex. Gold does not react with oxygen at any temperature [4] and, up to 100 °C, is resistant to attack from ...
Gold extraction is the extraction of gold from dilute ores using a combination of chemical processes. Gold mining produces about 3600 tons annually, [1] and another 300 tons is produced from recycling. [2] Since the 20th century, gold has been principally extracted in a cyanide process by leaching the ore with cyanide solution.
Another use of bisulfite in organic chemistry is as a mild reducing agent, for example to remove traces or excess amounts of chlorine, bromine, iodine, hypochlorite salts, osmate esters, chromium trioxide and potassium permanganate. Sodium bisulfite is a decoloration agent in purification procedures because it reduces strongly coloured ...
The Merrill–Crowe Process is a separation technique for removing gold from the solution obtained by the cyanide leaching of gold ores. It is an improvement of the MacArthur-Forrest process, where an additional vacuum is managed to remove air in the solution (invention of Crowe), and zinc dust is used instead of zinc shavings (improvement of Merrill).