Degussa Aktiengesellschaft

Alexander Ruhs

Rudiger Schutte

Claas-Jurgen Klasen

Ivan Pelgrims

Rainer Kohlen

Hans-Christian Alt

R&uuml;diger Sch&uuml;tte

Peter K Kleinschmit

Rudolf Schwarz

Birgit Bertsch-Frank

Wolfgang Leonhardt

Lothar Kaiser

The production of foam which occurs in many chemical and physical materials conversion processes can be avoided by performing the materials conversion process in an ascending jet reactor, including a baffle-free container with a tapering lower section, preferably a conical lower section, and a device for gas injection, and the contents of the reactor are thoroughly mixed by means of ascending jet circulation caused by gas injection.

Process for reducing or avoiding foam production during chemical and physical materials conversion processes

The invention relates to a fluidized bed reactor for the continuous production of fluidized bed granules. The reactor is characterized by a discharge device designed as a siphon pipe or siphon weir. The fluidized bed reactor permits a trouble-free continuous operation of the fluidized bed stage and of a connected, continuous subsequent stage. A preferred fluidized bed reactor comprises two chambers that are in communication via the discharge device according to the invention.

Fluidized bed reactor and a process of using the same

Process for reducing or avoiding foam production during chemical and physical materials conversion processes and a device for performing this process

Problems encountered when discharging bulk containers using a blow-through rotary valve can be avoided by the discharge device, according to the invention, in which a vent connection of the rotary valve is in connection with the internal chamber of the container through a filter hose open on both ends.

Discharge device for bulk containers for particulate bulk materials and

Method and apparatus for producing sodium perborate monohydrate by dehydrating sodium perborate tetrahydrate in a fluid bed with heated air. Contact surfaces are arranged inside the fluid bed whose total area is the same as up to 500 times the area of the approach-flow bottom of the fluid bed. The contact surfaces are advantageously designed as heat exchangers whose surface temperature is adjusted to maintain 90.degree. to 110.degree. C. at the contact surfaces. The method results in a sodium perborate monohydrate with especially high abrasion resistance. In addition, the energy requirement is lower than that provided in the previously known method commonly used in the industry.

Apparatus for producing sodium perborate monohydrate and product

Method for producing sodium perborate monohydrate

Particulate, active-oxygen compounds, especially sodium percarbonate, tend to cake during storage, which makes it more difficult to handle them. The invention reduces this caking tendency while the active-oxygen content remains essentially unchanged. The method of achieving this comprises bringing the active-oxygen compound in contact with such an amount of an aqueous solution containing one or more phosphonic acid compounds capable of chelate complex formation that the weight ratio of active-oxygen compound to phosphonic acid compound is 100:0.1 to 100:10, preferably 100:1 to 100:3, and subsequent drying. Sodium percarbonate is used in particular as active-oxygen compound and 1-hydroxyethane-1,1-diphosphonic acid as a 3 to 30% by weight aqueous solution is used as phosphonic acid compound. Sodium percarbonate wet salt is preferably washed with this solution, freed of excess solution and dried. Percarbonate treated in this manner hardly tends to cake at all and exhibits a greater active-oxygen stability.

Method of reducing the tendency of particulate active oxygen compounds

There is required titanium disulfide of high purity and stoichiometric composition as electrode material for certain types of batteries. With the known process for reacting preheated gaseous titanium tetrachloride with an excess of preheated gaseous hydrogen sulfide at 400.degree. to 600.degree. C., there is obtained a product which is not optimally usable. A titanium disulfide quality of higher purity and stoichiometry is obtained by forcing a deposition of the titanium disulfide on the inner walls of the reactor through regulating the temperature at the reactor walls and/or the residence time of the gaseous mixture. The titanium disulfide can be mechanically stripped off the walls and removed countercurrently to the waste gas stream from the reactor.

Growing community of inventors

Rheinfelden, Germany

Alexander Ruhs