Pidgeon

Three basic processes exist for the thermal reduction of magnesium oxide the Pidgeon process, the Magnetherm process, and the BoKano process. 

Pldgeon Process. The Pidgeon (46—49) process (Fig. 6) was the first commercial thermal reduction process usiag siUcoa, and was developed ia the 1940s. This process is used by Timminco (Haley, Oatario, Canada) and Ube Industries (Japan). The overall reaction for this process is... 

A vacuum-retort process (Pidgeon process) was used during World War II for the production of magnesium and calcium. SiHcon, in the form of ferrosihcon, was used as the reducing agent instead of carbon to avoid the problem of cooling magnesium vapor in the presence of carbon dioxide ... 

An industrial example of the reduction of stable oxides to form a metallic element as a vapour, is the Pidgeon process for the production of magnesium. 

Pidgeon, C., Venkataram, U. V. Immobilized artificial membrane chromatography supports composed of membrane lipids. Anal. Eiochem. 1989,... 

Thermal magnesium, i.e., magnesium produced by the Pidgeon process earlier and by the magnefherm process at present, constitutes only 30% of the total magnesium production. The rest is produced electrolytically in which the leading examples are (i) the Dow electrolytic reduction process, and (ii) Norsk hydro process. 

Examples of metals which are prepared by the metallothermic reduction of oxides include manganese, chromium, vanadium, zirconium, and niobium. In a manner similar to the production of magnesium by the Pidgeon process, some of the rare earth metals have been produced by the metallothermic reduction-distillation process. 

A very promising method, immobilized artificial membrane (IAM) chromatography, was developed by Pidgeon and co-workers [299-304,307], where silica resin was modified by covalent attachment of phospholipid-like groups to the surface. The retention parameters mimic the partitioning of drugs into phospholipid bilayers. The topic has been widely reviewed [47,298,307,309-311]. 

Pidgeon, C. Ong, S. Choi, H. Liu, H., Preparation of mixed ligand immobilized artificial membranes for predicting drug binding to membranes, Anal. Chem. 66, 2701-2709 (1994). 

Ong, S. Liu, H. Qiu, X. Bhat, G. Pidgeon, C., Membrane partition coefficients chromatographically measured using immobilized artificial membrane surfaces, Anal. Chem. 67, 755-762 (1995). 

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