Luwesta extractors

Podbielniak extractors Oelaval extractor Luwesta extractor Robatel extractor... 

The Luwesta extractor - 47 is a development of the Coutor extractor. 7 It is essentially a three-stage mixer-settler in which separation is carried out by centrifugal means, in a similar manner to a cream separator. Mixing occurs by means of a spray disc or alternatively when the two phases are collected simultaneously, in a collector disc. Light phase flows through the three stages in succession in one direction, and the dense phase in the opposite direction. 

Figure 14.15. A horizontal rotating extractor and two kinds of centrifugal extractors, (a) The RTL (formerly Graesser raining bucket) horizontal rotating extractor both phases are dispersed at some portion of the rotation RTL S. A., London). (b) Operating principle of the Podbielniak centrifugal extractor it is made up of several concentric perforated cylinders (Baker-Perkins Co.), (c) The Luwesta centrifugal extractor (schematic diagram) Luwa Corp.).

Luwesta (Centriwesta) Extractor This is a development from... 

The Luwesta (Centriwesta) extractor is a development from Coutor [Eisenlohr, Ind. Chem., 27, p. 271 (1951)]. This centrifuge revolves about a vertical axis and contains three actual stages. It operates at 3800 rotations per minute and handles approximately 5 mVh (1300 gal/h) total liquid flow at 12-kW power requirement. Provision is made in the machine for the accumulation of solids separated from the liquids, for periodic removal. It is used, more extensively in Europe than in tlie United States, for the extraction of acetic acid, pharmaceuticals, and similar products. 

Common penicillin extraction solvents are amyl- and butyl-acetate or methy-lisobutylketone. As penicillin is extracted as a free acid at pFl 2-2.5 and the molecule is instable at this pFl, extraction occurs in a counter-flow using Podbielniak- and Luwesta-centrifugal extractors to shorten the contact time with the solvent and to prevent product decomposition. 

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