Degussa Aktiengesellschaft

Degussa - Huls Ag

Evonik Degussa Gmbh

Ina Hemme

Steffen Hasenzahl

Birgit Bertsch-Frank

Herbert Habermann

Sven-Uwe Geissen

Anna Moiseev

Helmut Mangold

Torsten Balduf

Werner Wildner

Stipan Katusic

Georg Markowz

Martin Moerters

Rudiger Schutte

Uwe Diener

J&uuml;rgen Meyer

Rüdiger Schütte

Jürgen Rollmann

J&uuml;rgen Rollmann

Hilmar Gilges

Catrin Becker-Balfanz

Catrin Becker

Lukas Von Hoppel

Jurgen Rollmann

Reactions between at least two fluid reactants are performed in a reactor comprising wall elements (), slot-shaped reaction spaces () and cavities () for conducting a fluid heat-carrier through. Depending on the process and throughput, a modular structural design is chosen wherein an arbitrary number of wall elements () are assembled to a right-parallelepipedal block (), the reaction spaces () are formed between lateral surfaces () of right-parallelepipedal wall elements (), the reactants are introduced into the reaction spaces () from edge regions of one side of the block () and are conducted through the reaction spaces () in parallel flows and the fluid heat-carrier is conducted through the tubular cavities () extending in the interior of the wall elements ().

Process and device for carrying out reactions in reactor with slot-shaped reaction spaces

Silicon-titanium mixed oxide powder prepared by flame hydrolysis, having a ratio by weight of silicon dioxide/titanium dioxide, which is greater on the surface of the primary particles than that within the total primary particle. It is prepared by a flame hydrolysis process, in that a stream consisting of a vaporous titanium dioxide precursor and oxygen or an oxygen-containing gas and hydrogen, and a second stream consisting of a vaporous silicon dioxide precursor and a carrier gas consisting of oxygen, an oxygen-containing gas and/or an inert gas, are guided separately into the reaction chamber of a burner such as is known for the preparation of pyrogenic oxides, and are burnt here, the solid mixed oxide powder and hot gases are subsequently cooled, and the gases are separated from the solid. The powder may be used, for example, for the preparation of sunscreen preparations.

Silicon-titanium mixed oxide powder prepared by flame hydrolysis, which is surface-enriched with silicon dioxide, and the preparation and the use thereof

Pyrogenically prepared titanium dioxide doped by means of an aerosol contains an oxide from the group zinc oxide, platinum oxide, magnesium oxide and/or aluminium oxide as the doping component. It is prepared as follows: in the pyrogenic preparation of titanium dioxide, a metal salt solution is atomised to form an aerosol and injected into the production stream. The titanium dioxide may be used as a photocatalyst or as a UV adsorber or in processes for purification of waste water or waste air/gases.

Doped titanium oxides

Iron oxide-silicon dioxide-titanium dioxide mixed oxide is produced by burning vaporizable compounds of iron, silicon and titanium together in a hydrogen/oxygen flame. The mixed oxides may be used as UV absorbers in cosmetics.

Iron oxide and silicon dioxide-titanium dioxide mixed oxide

A process for the preparation of doped, pyrogenically prepared titanium dioxide is described. The titanium dioxide is doped with zinc oxide, platinum oxide, magnesium oxide, or aluminium oxide, by injecting an aerosol of the oxide into the production stream. The doped titanium dioxide may be used as a photocatalyst or UV absorber.

Doped titanium dioxide

Iron oxide-silicon dioxide-titanium dioxide mixed oxide is produced by burning vapourable compounds of iron, silicon and titanium together in a hydrogen/oxygen flame. The mixed oxides may be used as UV absorbers in cosmetics.

A process for photocatalytic removal of organic substances from waste waters, wherein by way of photocatalyst use is made of granulates based on pyrogenically prepared titanium dioxide having the following physicochemical characteristic data:

Photocatalytic process

A process for the direct synthesis of hydrogen peroxide from hydrogen and oxygen is carried out in the presence of a noble metal catalyst. The selectivity for H and/or the maximum H O concentration can be increased by using a catalyst of palladium or at least two metals selected from Group VIII and Group I of the Periodic Table of Elements, which catalyst has been produced by spray pyrolysis or flame pyrolysis.

Process for producing hydrogen peroxide by direct synthesis

An aqueous solution of hydrogen peroxide is produced by direct synthesis from hydrogen and oxygen in the presence of a heterogeneous catalyst. According to the invention, a gas mixture comprising H.sub.2 and O.sub.2, essentially saturated or supersaturated with water (=containing fog) is fed into a reactor containing the catalyst. The volume ratio of the gas mixture fed in (standard liters per hour) to liquid removed (liters per hour) is adjusted to a value equal to or greater than 15,000, especially 20,000 to 50,000, and the gas mixture leaving the reactor is recycled after replenishment with H.sub.2, O.sub.2, and H.sub.2 O vapor. Solutions with high H.sub.2 O.sub.2 concentration can be obtained according to the invention without additional concentration.

Growing community of inventors

Hanau, Germany

Ina Hemme