Akzo Nobel N.v.

Martin Nywlt

Manfred F Bergfeld

Michael Diamantoglou

Winfried Holz

A method for producing cellulosic dialysis membranes in the form of flat, tubular, or hollow fiber membranes by spinning a spinning solution of cellulose and/or modified cellulose, a tertiary amine oxide, and additional liquids and additives such as stabilizers, pore formers and the like is provided. The method operates at high takeoff speed and produces membranes for the low, middle, and high flux ranges. The membranes show practically no aging and have a stable structure. The oxidative breakdown of cellulose in the manufacture of the membranes is extremely low and hemocompatability is very good.

Method of making cellulosic dialysis membrane

The invention relates to a method for manufacturing tert-butylamine from isobutene and ammonia in the presence of a silica alumina catalyst. The catalyst is in acid form, has an Si/Al ratio that has been adjusted by steam dealumination, has a crystallinity of at least 95%, and has an Na.sub.2 O content of less than 0.2 wt. %. The reaction is preferably conducted in the gas phase, with unreacted ammonia and unreacted isobutene being recycled into the reaction process. The selectivity of the catalyst for the formation of tert-butylamine is at least 99.5%.

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Obernburg, Germany

Martin Nywlt