Umicore Ag & Co Kg

Degussa Aktiengesellschaft

Omg Ag & Co Kg

Dmc2 Degussa Metal Catalysts Cerdec Ag

Michael Harris

Thomas Kreuzer

Egbert Lox

Dieter Detterbeck

Lothar Mussmann

Dieter Lindner

Yvonne Demel

Josef Piroth

Ralph Kiessling

J&uuml;rgen Leyrer

Disclosed is a method and a corresponding apparatus for coating open-pored bodies with at least one coating suspension, the coating suspension having solids and solutes in a liquid medium in a quantity in wet state which is to correspond to at least a required target quantity, and the coating operation having a variation in the applied wet coating quantity from one body to the other. The method includes steps of: coating the body with an actual quantity of the coating suspension, which is always larger than the required target quantity taking the variation of the coating operation into account, determining the difference between the actual quantity and the required target quantity, and reducing the difference between actual quantity and target quantity by removing still wet coating suspension.

Method and apparatus for coating a carrier

This invention relates to a method and a corresponding apparatus for coating open-pored bodies with at least one coating suspension. In particular, the coating suspension has solids and solutes in a liquid medium in a quantity in wet state which is to correspond to at least a required target quantity. The coating operation has a variation in the applied wet coating quantity from one body to the other. The method according to the invention is characterized by the steps of: coating the body with an actual quantity of the coating suspension, which is always larger than the required target quantity taking the variation of the coating operation into account, determining the difference between the actual quantity and the required target quantity, and reducing the difference between actual quantity and target quantity by removing still wet coating suspension.

The invention provides a process for coating a cylindrical carrier structure with a predetermined amount (target take-up) of a coating suspension, wherein the carrier structure has a cylinder axis, two end faces, an encasing face and an axial length L and a large number of channels running from the first end face to the second end face. The process comprises: a) vertically aligning the cylinder axis of the carrier structure and filling the empty volume of the channels up to a predetermined height H starting from the lower end face, b) removing the excess coating suspension through the lower end face of the carrier structure down to the target take-up, c) turning the carrier structure 180&deg;, so that the upper and lower end faces are exchanged one for the other, and d) repeating steps a) and b), wherein the height H , up to which the channels are filled in this case is given by H &equals;L&minus;x&middot;H where x is between 0.8 and 1.0.

Process for coating a carrier structure

A structured catalyst for selective reduction of nitrogen oxides with ammonia using an ammonia-supplying compound. The catalyst is preferably used for exhaust gas treatment of diesel vehicles powered by diesel motors. The catalyst is characterized by the fact that it contains a reduction catalyst for selective reduction of nitrogen oxides with ammonia and a hydrolysis catalyst for the hydrolysis of urea, where the hydrolysis catalyst is applied in the form of a coating onto the reduction catalyst. By this arrangement of the two catalytic functions in one catalyst the exhaust gas system can be made very compactly and space saving. Moreover, advantageous synergistic effects result from the direct contact of the hydrolysis catalyst and the reduction catalyst.

Structured catalysts for selective reduction of nitrogen oxides by ammonia using a compound that can be hydrolyzed to ammonia

A catalyst for treating exhaust gas from an internal combustion engine includes a carrier body coated with an inner layer and an outer layer. The inner layer includes platinum deposited on a first support material and on a first oxygen storage component, and the outer layer includes platinum and rhodium deposited on a second support material and on a second oxygen storage component. The first and second support materials may be the same or different, and may be selected from the group of: silica, alumina, titania, zirconia, mixed oxides or mixtures thereof, and zirconia-rich zirconia/ceria mixed oxide. The first and second oxygen storage components may include ceria-rich ceria/zirconia mixed oxide compounds, optionally including praseodymia, yttria, neodymia, lanthana or mixtures thereof.

Growing community of inventors

Lörrach, Germany

Michael Harris