Abstract: The present invention discloses a microreactor for performing heterogeneous catalytic reactions, being of plate or stack construction for industrial use, with provision made for chambers between the plates for the chemical reaction and for the heat removal. Inside the reaction chambers, catalyst material is applied to the internal walls or filled into recesses, and in all chambers there are spacers. In particular the slot-shaped reaction chambers have channels with a hydraulic diameter smaller than 1500 ?m and a ratio of free slot width to free slot height in the range of 10 to 450.

Abstract: A process for the selective catalytic reduction of nitrogen oxides with ammonia in a lean-mix exhaust gas from a combustion process operated with a first, lean-mix air/fuel mixture, wherein the ammonia required for selective reduction is obtained from a second, rich-mix air/fuel mixture which contains nitrogen monoxide by reduction of the nitrogen monoxide in a NH3 synthesis step to give ammonia with the formation of a product gas stream, and where the nitrogen monoxide-containing second air/fuel mixture is supplied to the NH3 synthesis step for reduction of the nitrogen monoxide to ammonia over a three-way converter catalyst and the ammonia formed is separated from the product gas stream and is stored in a storage medium for use as and when required for selective catalytic reduction.

Abstract: Reactions between at least two fluid reactants are performed in a reactor comprising wall elements (1), slot-shaped reaction spaces (3) and cavities (5) 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 (1) are assembled to a right-parallelepipedal block (24), the reaction spaces (3) are formed between lateral surfaces (2) of right-parallelepipedal wall elements (1), the reactants are introduced into the reaction spaces (3) from edge regions of one side of the block (24) and are conducted through the reaction spaces (3) in parallel flows and the fluid heat-carrier is conducted through the tubular cavities (5) extending in the interior of the wall elements (1).

Abstract: The present invention discloses a microreactor for performing heterogeneous catalytic reactions, being of plate or stack construction for industrial use, with provision made for chambers between the plates for the chemical reaction and for the heat removal. Inside the reaction chambers, catalyst material is applied to the internal walls or filled into recesses, and in all chambers there are spacers. In particular the slot-shaped reaction chambers have channels with a hydraulic diameter smaller than 1500 ?m and a ratio of free slot width to free slot height in the range of 10 to 450.

Abstract: A modular construction micro-reactor with parallel microchannels on fluid guide plates for chemical reactions, but not for evaporation purposes is known. A modular construction falling film evaporator is disclosed, comprising a stack of alternate gap-like evaporation chambers and sheet-like evaporator modules with an assembly of parallel microchannels, whereby the evaporation chambers are open above and/or below across the whole width of the module and the stack is arranged in a container. The falling film evaporator is used in a method for obtaining a gaseous phase from a liquid medium on a technical scale and is suitable for the concentration of thermolabile solutions and rapidly adjustable production of a gas stream.

Abstract: 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.

Abstract: A bubble column can be operated using countercurrent flow including perforated trays. The space-time yield of gas-liquid reactions can be considerably increased if the perforated trays have a substantially uniform distribution of holes, if the cross-sectional area of the individual holes is 0.003 to 3 mm2, particularly 0.01 to 0.5 mm2, and if the open area of the trays is 3 to 20%, particularly 3 to 10%, and if the bubble column comprises passages for liquid between adjacent liquid zones. The bubble column can be used for carrying out gas-liquid reactions, such as oxidation reactions with air, with the gas and liquid preferably being passed in countercurrent flow through the column. Cocurrent flow may also be used.

Abstract: A method for epoxidation of olefins with 2 to 6 C atoms, especially propene, with hydrogen peroxide in the gas phase at a temperature below 250° C. The reaction is carried out by bringing a gas mixture containing the olefin, hydrogen peroxide and water into contact with the catalyst from the series of compounds of an element of the 4th to the 6th subgroup of the periodic table or of arsenic or selenium and molecular sieves in the absence of a liquid phase. Titanium-containing molecular sleeves are preferred catalysts.

Abstract: 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.

Abstract: In order to increase active oxygen stability, sodium percarbonate is coated with single or multiple layers of various substances. Sodium percarbonate particles consist of a core of sodium percarbonate fluidized bed spray granulate and sodium sulphate, which may be partially hydrated, as the sole constituent of a single coating layer. The particles exhibit both elevated active oxygen stability and very good ensilability. The coating layer is applied by spraying an aqueous Na.sub.2 SO.sub.4 solution onto the particles to be coated, which were themselves produced by fluidized bed spray granulation, in a fluidized bed and vaporizing water at a fluidized bed temperature of 35 to 100.degree. C.

Abstract: New alkali metal cyanide granulates based on sodium cyanide or potassium cyanide and a method for their preparation are disclosed. Commercially available alkali metal cyanide granulates consist of irregular particles; disadvantages are in particular the tendencies to form dust and to cake. The disclosed alkali metal cyanide granulates demonstrate a reduced tendency to cake and virtually no abrasion. The granulates are characterized by essentially spherical particles with particle diameters in the range 0.1 to 20 mm, a bulk density of more than 600 g/dm.sup.3, an abrasion of less than 1%, and a caking index of at most 4. The granulates can be prepared by fluidized bed spray granulation involving spraying an aqueous solution containing alkali metal cyanide onto alkali metal cyanide nuclei in a fluidized bed and evaporating the water.