Degussa Aktiengesellschaft

Degussa - Huls Ag

Evonik Degussa Gmbh

Degussa Aktiengsellschaft

Mustafa Siray

Peter K Kleinschmit

Karl Meier

Robert Kuhlmann

Gunter Turk

Anke Blume

Heinz Esch

Stefan Uhrlandt

Udo Goerl

Burkhard Freund

Gerold Schmidt

Jochen Scheffler

Andrea Hunsche

Hartwig Rauleder

Edgar Koberstein

Bernd Engler

Akos Kiss

Christian Panz

Markus Ruf

Michael Baacke

Thomas Barthel

Bodo Frings

Bernhard Schwaiger

Florian Paulat

Jürgen Behnisch

Guido Titz

Peter Erlhöfer

Jurgen Behnisch

Sven Müller

Reinhold Beand

Peter Kleine-Mollhoff

Sven Muller

Peter Erlhofer

The present invention relates to a method of purifying strong acids or strongly acidic media to remove di- and higher valent metal ions, which can be used within the context of the production of high-purity silica. The invention further relates to the use of special ion exchangers for carrying out the method according to the invention and the resultant high-purity silicas.

Method for the separation of metal ions that are divalent or higher from strong acids or highly acidic media

Precipitated silica

Precipitated silicic acid

Readily dispersible precipitated silica

A process for preparing microporous separating elements for batteries by intensive mixing of a high molecular weight polyethylene with a precipitated silica having specific chemical and physical characteristics, a process liquid and a stabilizer to form a powder mixture, which is extruded to form a film, from which the process liquid is removed, thereby leaving the desired microporous separating elements which are recovered.

Precipitated silicas, characterized in that they have a CTAB surface area (in accordance with ASTM D 3765-92) of 200 to 400 m.sup.2 /g, a DBP index (in accordance with ASTM D 2414) between 230 and 380 ml/100 g as powder and 180-250 g/100 g as granulate, a silanol group density (V.sub.2 -NaOH consumption) of 20 to 30 ml and the following macropore size distribution which is typical of the surface area range involved, determined by means of Hg porosimetry (DIN 66 133) for specific pore size intervals (incremental mode of application):

Precipitated silicas, a process for their preparation and their use in

Precipitated silica with the following physical-chemical characteristics:

A zeolite catalyst and a method for reduction of nitrogen oxides present in waste gas streams is described. The method includes mixing the waste gas containing nitrogen oxides with ammonia. At an elevated temperature, this mixture is passed over a zeolite catalyst. Preferably, the zeolite catalyst is in a monolithic or honeycomb form. The zeolite catalyst includes one or more of the following subgroup metals: copper, iron, molybdeum and cerium. The zeolite catalysts made in accordance with this invention show better conversion of nitrogen oxides and longer life than known catalysts.

Method for the reduction of nitrogen oxides from waste gases using a

A method for producing tetrapropylammonium bromide by reacting tripropylamine with propyl bromide in a polar solvent at a temperature between 60.degree. and 160.degree. C.

Method for producing tetrapropylammonium bromide

Growing community of inventors

Bonn, Germany

Mustafa Siray