Degussa Aktiengesellschaft

Hoechst Aktiengesellschaft

Reinhard Manner

Peter K Kleinschmit

Dietrich Arntz

Gunter Prescher

Werner Burkhardt

Carl Voigt

Felix Schmidt

Gerhard Birtigh

Johannes Heilos

Reinhard Klingel

Ewald Dittrich

Hans Schaefer

Wolf D Pfeifer

Herbert Ginter

Jurgen Dorr

Walter Barthel

Wolfgang Eckert

Gunter Frankfurter

Ivo Daniels

Karl H Mueller

Gerhard Dusing

Reinhard Klingle

Carl Voight

Wilfried Baumgartner

A method for the uniform coating of honeycomb bodies with finely divided solid matter from a dispersion in an amount which is below that which arises during customary immersion. To this end, the honeycomb is flooded from below with dispersion, emptied after a dwell time and blown out. Filling time, filling amount, dwell time emptying time as well as the time between emptying and blowing out are measured in such a manner that in order to increase the separated amount of solid matter, filling time, dwell time, pumping-out time and the time between emptying and blowing out are increased but the filling amount is reduced.

Method of coating honeycomb bodies with finely divided solid matter

An apparatus and a method are disclosed for the removal and the recovery of washcoat remaining in the channels of freshly coated monolithic or honeycombed catalytic carriers. The carrier is inserted into a chamber from above and tightly fitted therein at least with the lowest part of the carrier therein. The chamber is fitted with a collection area and a runoff located thereunder. The runoff leads via a shutoff valve into a separation vessel under a vacuum. The opening and closing of the shutoff valve causes air to be aspirated through the carrier channels, which are open at the top or are gradually opened by means of a slotted slide. This action causes the washcoat remnants to be transferred into the separation vessel, where they can be collected in the sump and are then pumped off. The apparatus can be used in systems for manufacturing catalysts for cleaning exhaust gases.

Method for removing washcoat remaining in the channels of freshly coated

A gas-tight aluminum oxide tube having an Al.sub.2 O.sub.3 content of 98.0 to 99.8 wt-%, wherein the interior of the tube has a coating of Al.sub.2 O.sub.3 with a thickness of from 0.03 to 0.30 mm and a mean roughness R.sub.a of 2 to 10 .mu.m, is provided. Preferably, the outer surface of the tube can have a mean roughness of 1.0 to 1.5 .mu.m. Also, the coating material can contain from 15 to 30 vol-% pores and the tube material can contain from 5 to 10 vol-% pores.

Aluminum oxide tubes

Apparatus and method for removing washcoat remaining in the channels of

A free-flowing granular bitumen product containing from 0.5 to 6% by weight of a powdery coating and separating agent such as synthetic silica or carbon black is prepared by atomizing hot, liquid bitumen in a spray mixer while simultaneously introducing the powdery coating and separating agent by means of the cold air flow into the spray mixer.

Granular bitumen coated with carbon black or silica

Pyrogenically prepared silicic acid is compressed by a rotary filter equipped with a pressing band.

Method of compressing pyrogenically prepared silicic acid

There is obtained an increase in the throughput in the known BMA furnace or a BMA furnace chamber without changing the construction and dimensions already present by changing the lower part of the cooling head into a short tubular heat exchanger while maintaining the necessary temperature profile for the process by arranging the ceramic tubes in the furnace chamber in closer or less close fashion and/or by using ceramic tubes having different inner and outer geometries and/or structure.

Process & apparatus for the production of hydrogen cyanide

There are prepared zeolite molded articles which also contain alkali silicate and/or alkaline earth silicate and mineral fibers and/or carbon fibers in addition to the zeolite.

Method of making zeolite castings

A method for compacting and/or filling of pulverulent materials into rigid or flexible containers in the course of which the pulverulent material is filled into the container with the help of a pipe in relative motion to the container, and separated from the gas, for example air, transported along with the help of a separation device which surrounds the pipe and is fitted to the container cross section. The pulverulent material is retained in the container with the help of the separation device, while the gas escapes through the gas permeable separation device.

Process for compacting and/or filling up pulverulent material

Zeolite castings

A powdery substance, such as for example pyrogenically prepared silicon dioxide, is subjected to predensification through the utilization of centrifugal force in a centrifuge. Subsequently, the centrifuge receptacles are closed with a free flying piston. Through utilization of the centrifugal force, there is achieved through the use of the free flying piston an additional pressure which is exerted on the predetermined powdery substance.

Method for densification of powdery silica and article formed thereby

A process is disclosed for preparing coated catalysts, inter alia, for gas phase oxidations in organic chemistry, comprised of an inert support and a coating of catalyst material enclosing this support, wherein a suspension of the starting material for the coating is sprayed onto an agitated bed of the support, while the suspending medium is being partially removed by a gas stream, and the raw material is then dried and heat-treated. For this purpose, the support bed is mechanically agitated and loosened by a gas stream blown in from below. The catalyst precursor containing a binder and, if appropriate, a pore-former is sprayed in an increasing amount from above onto the bed, the ratio between suspending medium sprayed on and drawn off remaining about constant. The thermal expansion coefficient of the precursor as a dry powder must not deviate by more than 15% from that of the support. The applied coating is densified by continuing the mechanical and fluidizing mixing motion, the material is then dried in a continuing gas stream and heat-treated, if appropriate after decomposition of an added pore-former.

Process for preparing abrasion-resistant coated catalysts

Process and apparatus for the production of hydrogen cyanide

A process is disclosed for preparing coated catalysts, inter alia, for gas phase oxidations in organic chemistry, comprised of an inert support and a coating of catalyst material enclosing this support, wherein a suspension of the starting material for the coating is sprayed onto an agitated bed of the support, while the suspending medium is being partially removed by a gas stream, and the raw material is then dried and heat-treated. For this purpose, the support bed is mechanically agitated and loosened by a gas stream blown in from below. The catalyst precursor containing a binder and, if appropriate, a pore-former is sprayed in an increasing amount from above onto the bed, the ratio between suspending medium sprayed on and drawn off remaining about constant. The thermal expansion coefficient of the precursor as a dry powder must not deviate by more than 15% from that of the support. The applied coating is densified by continuing the mechanical and fluidizing mixture motion, the material is then dried in a continuing gas stream and heat-treated, if appropriate after decomposition of an added pore-former.

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Maintal, Germany

Reinhard Manner