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The Reformatsky reaction (sometimes transliterated as Reformatskii reaction) is an organic reaction which condenses aldehydes or ketones with α-halo esters using metallic zinc to form β-hydroxy-esters: [1] [2] The Reformatsky reaction. The organozinc reagent, also called a 'Reformatsky enolate', is prepared by treating an alpha-halo ester ...
The Waelz process is a method of recovering zinc and other relatively low boiling point metals from metallurgical waste (typically electric arc furnace flue dust) and other recycled materials using a rotary kiln (waelz kiln). The zinc enriched product is referred to as waelz oxide, and the reduced zinc by product as waelz slag.
This organic reaction can be employed to convert α-haloester and ketone or aldehyde to a β-hydroxyester. Acid is needed to protonate the resulting alkoxide during work up. The initial step is an oxidative addition of zinc metal into the carbon-halogen bond, thus forming a carbon-zinc enolate.
Was one of the big three spreadsheets (the others being Lotus 123 and Excel). EasyOffice EasySpreadsheet – for MS Windows. No longer freeware, this suite aims to be more user friendly than competitors. Framework – for MS Windows. Historical office suite still available and supported. It includes a spreadsheet.
It forms on the surface of low-melting-point metals such as tin, lead, zinc or aluminium or alloys by oxidation of the metal. For higher melting point metals and alloys such as steel and silver, oxidized impurities melt and float making them easy to pour off. With wrought iron, hammering and later rolling remove some dross. [1]
The Tipson–Cohen reaction is a name reaction first discovered by Stuart Tipson and Alex Cohen at the National Bureau of Standards in Washington D.C. [1] The Tipson–Cohen reaction occurs when two neighboring secondary sulfonyloxy groups in a sugar molecule are treated with zinc dust (Zn) and sodium iodide (NaI) in a refluxing solvent such as N,N-dimethylformamide (DMF) to give an ...
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).
Zinc is extracted from the purified zinc sulfate solution by electrowinning, which is a specialized form of electrolysis. The process works by passing an electric current through the solution in a series of cells. This causes the zinc to deposit on the cathodes (aluminium sheets) and oxygen to form at the anodes. Sulfuric acid is also formed in ...