Abstract: 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 H2 and/or the maximum H2O2 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.

Abstract: The precipitated silica has the following physico-chemical parameters: BET surface area (DIN 66131) in m2/g 400-600 DBP index (DIN 53601) in g/100 g 300-360 Compacted density (DIN 53194) in g/l  70-140 Grindometer value (ISO 1524) in &mgr;m 15-50 Size distribution index I <1.0 measured with a Malvern instrument Size ⁢   ⁢ distribution ⁢   ⁢ index ⁢   ⁢ I = d 90 - d 10 2 ⁢ d 50 This precipitated silica is prepared by milling a precipitated silica in accordance with DE-A 31 44 299 in a classifier mill or a fluidized bed counter-flow mill.

Abstract: Organosilicon compounds of general formula (I) R1R2R3Si—R4—S—Zn—S—R4—SiR1R2R3  (I) wherein R1, R2, R independently, represent H, a halogen, alkyl or alkoxy and R4 represents an alkylidene group, their preparation and their use in rubber mixtures.

Abstract: A process for the preparation of epoxides by epoxidation of olefinic compounds with hydrogen peroxide in the presence of a titanium silicalite as a catalyst. A base is introduced into the epoxidation reactor directly or as a mixture with one or more starting substances, under pH control. A pH in the range from 4 to 9.5, preferably a pH of 5 to 9.5, is established and maintained in the reaction mixture or in the starting substance containing the base. Preferably, an aqueous-organic hydrogen peroxide solution with a pH in the range from 8 to 9 is employed and the epoxidation is carried out in a fixed bed reactor.

Abstract: Raney copper which is doped with at least one metal from the group comprising iron and/or noble metals is used as a catalyst in the dehydrogenation of alcohols.

Abstract: This invention relates to a process for the production of L-amino acids using coryneform bacteria, in which the glutamate dehydrogenase gene is amplified.

Abstract: The present invention is relative to a method for the homogeneous, catalytic, enantioselective hydrogenation of compounds of the general formula (I) with the aid of compounds of the general formula (II) The use of the hydrogenated derivatives in organic synthesis.

Abstract: A process for the production of 2,3,5-trimethylhydroquinone diesters by aromatization of 2,6,6-trimethyl-2-cyclohexene-1,4-dione (4-oxoisophorone, ketoisophorone, KIP) with an acylating agent and an acidic soluble or insoluble catalyst, which process may be operated alternatively continuously or discontinuously. The process includes the following steps: a) a carboxylic anhydride having a C1 to C4 alkyl residue is used as the acylating agent, b) after the reaction, a proportion of the resultant carboxylic acid is optionally removed by distillation, c) the reaction solution is cooled, d) the product which has crystallized out is separated and washed, and e) the filtrate is returned to step a).

Abstract: The use of the ligands and complexes of general formula I and II for catalytic, enantioselective hydrogenation.

Abstract: A process for preventing the transfer of harmful organisms of zooplankton including the epifauna thereof and of phytoplankton including its resting stages, which are taken up with the ballast water of ships and transferred to another locality on discharge. The organisms are substantially destroyed by the addition of an agent containing a water-soluble percarboxylic acid with 1 to 6 carbon atoms, particularly an aqueous solution containing peracetic acid and/or performic acid and hydrogen peroxide, in a quantity of 0.1 to 200 mg of percarboxylic acid per liter of ballast water and allowing it to react before discharge. In a preferred embodiment, cyanide is also added to the ballast water.

Abstract: The present invention relates to a process for the preparation of &ggr;-lactams of the general formula I The invention relates also to novel advantageous intermediates of the general formulae V, IV and II and their salts and their use. The compounds of the general formula I are obtained by cyclising compounds of the general formula II which can be prepared from the intermediate compounds V.

Abstract: Process for the production of polysulfide silane compounds of the general formula Z-R1-Sn-R1-Z  (I) wherein silylalkyl halides of the formula ZR1X  (II) are reacted with alkali metal polysulfides of the formula M2Sn,  (III) wherein alkali metal polysulfides M2Sn are obtained by reacting alkali metal hydroxides of the general formula (IV) MOH  (IV) and elemental sulfur in a non-aqueous solvent or without solvent.

Abstract: A method for producing alkali metal salts or alkaline earth metal salts of 2,4-dicloro-6-hydroxy-s-triazine, especially the sodium salt, by reacting cyanuric chloride with an alkali hydroxide or alkaline earth hydroxide. 1 to 2.5 Equivalents of alkali hydroxide or alkaline earth hydroxide per mole cyanuric chloride in the form of an aqueous solution or suspension are placed in a receiver and cyanuric chloride in powder form or in the form of an aqueous suspension is added while maintaining a pH in the range of 9.5 to 14 and cooling. If less than a stoichiometric amount is added to the receiver, the remaining amount of alkali hydroxide or alkaline earth hydroxide is added during and/or after the addition of cyanide chloride, while maintaining the pH. The method can be carried out on an industrial scale and formation of the salt of monochlorodihydroxytriazine is largely avoided.

Abstract: A boron oxide-silicon dioxide mixed oxide which has a BET surface of less than 100 m2g, and optionally containing oxides of aluminium, titanium or zirconium, is prepared pyrogenically by flame hydrolysis. The mixed oxide is used in glass making.

Abstract: The invention provides a feedstuff additive based on a fermentation broth which is obtained by the fermentation of D-pantothenic acid producing microorganisms and contains one or more salts of D-pantothenic acid, selected from the group of sodium, potassium, ammonium, magnesium or calcium salts.

Abstract: A process for the preparation of compounds of the general formula (I) by reacting an aldehyde compound of the general formula (II) with a urea compound of the general formula (III) in the presence of carbon monoxide and a catalytically active metal compound. Compounds of the general formula (I) are important intermediates for the synthesis of &agr;-amino acids.

Abstract: Reduction in the content of acetals or ketone acetals in a reaction mixture containing at least 10 moles alcohol per mole acetal or ketone acetal can be achieved hydrogenolytically when the reaction mixture is hydrogenated at 80° to 250° C. at a hydrogen partial pressure of 0.5 to 30 MPa in the presence of activated carbon charged with noble metal as catalyst.

Abstract: A process for continuous dry granulation of powdered carbon black. Granulation is performed with the assistance of a granulator. As a result, for comparable sized equipment, the carbon black throughput can be increased several times as compared with pelletizing drums used in the conventional manner.

Abstract: An electrolysis cell for carrying out chemical reactions include an electrolyte chamber (2) with a fixed-bed electrode (2F), a gas chamber (1) filled with filling bodies (1F), a gas diffusion electrode with an ion-exchanging separator (3) applied on the electrolyte-chamber side. The ion-exchanging separator is applied onto the gas diffusion electrode by a method comprising a single or multiple application of a solution of an ion-exchanging material in a solvent onto the electrocatalytically active layer of the gas diffusion electrode and at least partial evaporation of the solvent after each coating. The electrolysis cell may be used for the oxidation and reduction of organic or inorganic components dissolved in the electrolyte.

Abstract: A precipitated silica which contains an active substance with a characteristic, delayed release of active substance is prepared by adding the active substance during preparation of the precipitated silica. The precipitated silica containing the active substance may be added to oral hygiene agents such as toothpastes, topical fluoride preparations, dental materials or medicinal chewing gums.