Dormagen process

In the so-called Dormagen process developed by IG Farben the cotton was first preheated with 30-40% of its own weight with glacial acetic acid for 1-2 hours. The pretreated material was then fed to the acetylisers, which consisted of horizontal bronze cylinders. For every 100 parts of pretreated cellulose there was added the following acetylating mixture, previously cooled to 15-20°C ... 

Current acetylation techniques may be based on continuous production similar to that employed in the Dormagen process or batchwise in dough-type mixers. 

The Bayer process operates in the liquid phase at lOO C, in the presence of an ion exchange resin. With a very high conversion ratio (99 per ccntX 75 mole per cent of dimers and 25 per cent of trimers are formed. A 90.000 t/year unit operates on this process in Dormagen [Erdolchemie). The main market for isooctenes is nonyl alcohol, which is used to synthesize plasticizers. 

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