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Karim Zaghib was born in Constantine and grew up in Setif, Algeria. [3] He obtained the D.E.A. degree in 1987 and the Ph.D. degree in Electrochemistry under the direction of Prof. Bernadette Nguyen in 1990, both from the Grenoble Institute of Technology, and the Habilitation degree in Physics from Pierre and Marie Curie University (Paris VI) in 2002.
Zinc smelting is the process of converting zinc concentrates (ores that contain zinc) into pure zinc. Zinc smelting has historically been more difficult than the smelting of other metals, e.g. iron , because in contrast, zinc has a low boiling point .
Immersion zinc plating is an electroless (non-electrolytic) coating process that deposits a thin layer of zinc on a less electronegative metal, by immersion in a solution containing a zinc or zincate ions, Zn(OH) 2− 4. A typical use is plating aluminum with zinc prior to electrolytic or electroless nickel plating.
Zinc refining is the process of purifying zinc to special high grade (SHG) zinc, which is at least 99.995% pure. [1] This process is not usually required when smelting of zinc is done through electrolysis processes, but is needed when zinc is produced by pyrometallurgical processes, because it is only 98.5% pure.
The concept of using a rotary kiln for the recovery of Zinc by volatization dates to at least 1888. [1] A process was patented by Edward Dedolph in 1910. Subsequently, the Dedpolph patent was taken up and developed by Metallgesellschaft (Frankfurt) with Chemische Fabrik Griesheim-Elektron but without leading to a production scale ready process.
The Albion process is an atmospheric leaching process for processing zinc concentrate, refractory copper and refractory gold. [1] The process is important because it is the most cost-effective method currently in use for extracting both the zinc and lead from concentrates that contain high lead levels (7% or greater).
A single-displacement reaction, also known as single replacement reaction or exchange reaction, is an archaic concept in chemistry. It describes the stoichiometry of some chemical reactions in which one element or ligand is replaced by atom or group. [1] [2] [3] It can be represented generically as:
The key zinc-intermediate formed is a carbenoid (iodomethyl)zinc iodide which reacts with alkenes to afford the cyclopropanated product. The rate of forming the active zinc species is increased via ultrasonication since the initial reaction occurs at the surface of the metal.