Degussa Aktiengesellschaft

Evonik Degussa Gmbh

Degussa - Huls Ag

Degussa Aktiengellschaft

Martin Trageser

Peter Werle

Hans-Peter Krimmer

Oswald Helmling

Harald Jakob

Martin Roos

Manfred Schmidt

Friedhelm Merz

Klaus Stadtmueller

Hans Peter Krimmer

Hermann Piana

Franz-Rudolf Kunz

Judith N J&oslash;rgensen

Ulrike Duderstadt

Michael Beck

Werner Pahling

Bernd Geissler

Harold Jakob

Klaus STADTMÜLLER

The invention is directed to an improved, reliably performable process for preparing triallyl isocyanurate (TAIC) by Cu-catalysed rearrangement of triallyl cyanurate (TAC) at at least 90&#xb0; C. According to the invention, TAC and, if required, also a Cucatalyst and solvent are fed continuously to a start reaction mixture after onset of the initially inhibited isomerization reaction, the isomerization is performed at from 90 to 160&#xb0; C. and an amount of reaction mixture equivalent to the amount of reactant is drawn off continuously and sent to the workup. Preference is given to effecting the isomerization in TAIC as the reaction medium.

Process for preparing triallyl isocyanurate (TAIC)

The present invention is directed towards a method for the production of 2,4,6-trimercapto-1,3,5-triazine (TMT-H). In particular, the method of the subject matter relates to the operation of acidifying the salts of 2,4,6-trimercapto-1,3,5-triazine in aqueous solution and in a defined pH range.

Method for the production of 2,4,6-trimercapto-1,3,5-triazine

The present invention is directed to a process for preparing amides. In particular, the process is directed to a process performable on the industrial scale, in which a ketoxime can be converted to a cyclic or acyclic amide by means of a Beckmann rearrangement using 2,4,6-trichloro-1,3,5-triazine as a catalyst in a nonpolar organic solvent.

Process for preparing amides from ketoximes

Powdered mixtures of chlorhexidine base with selected sugar acids or lactones from the group gluconic acid or gluconolactone, lactobionic acid (I), D-galactono-&ggr;-lactone (II), L-mannono-&ggr;-lactone (III), D-(&minus;)-gulono-&ggr;-lactone (IV), D-(&plus;)-galacturonic acid (V) and &agr;-D-heptaglucono-&ggr;-lactone (VI). The formulations have extraordinary storage stability. New chlorhexidine salts with sugar acid anions based on (I) to (VI) and aqueous solutions of these are also described. The formulations, solutions and pure salts are used as disinfectants and to prepare disinfectants.

Chlorhexidine formulations, new chlorhexidine salts, solutions containing these and their use

Acrolein polymer from acrolein and one or more polyhydric alcohols, characterized by release of monomeric acrolein in aqueous systems and hence by a prolonged effect on microorganisms, is prepared by adding acrolein to a reaction medium containing catalyst in dissolved form, and not allowing the temperature of the reaction medium to rise about 50.degree. C. The acrolein polymer may be used in aqueous systems as a biocide.

Acrolein-releasing copolymers

Acrolein-releasing emulsion homopolymers release acrolein in aqueous systems. They are produced by adding acrolein, at least 95% by weight pure, to a solution of an alkali hydroxide, with the temperature not exceeding 25.degree. C. during the addition, and then adjusting the pH to 5 to 7 by adding a mineral acid.

Acrolein-releasing emulsion homopolymers

A composition which is capable of releasing acrolein and is easy to handle contains (i) an acetal of acrolein with a C.sub.1-6 alcohol with 1 to 4 hydroxyl groups and (ii) an acid soluble therein and chemically compatible with a pK.sub.s value of less than 4 and (iii) is anhydrous. A preferred composition contains 2-vinyl-1,3-dioxolane as acetal, anhydrous oxalic acid, fumaric acid or maleic acid or a mixture of mono- and di(C.sub.1 - to C.sub.3 -)alkyl phosphate as acid and, in addition, a non-ionic surfactant. The acrolein is released at the site of use upon contact with for example water for the purpose of combatting microbial, vegetable and animal pests.

Composition capable of releasing acrolein and its use

The direct handling of acrolein for the purpose of combatting microbial, vegetable and animal pests in water and soil is problematic on account of the potential for danger of acrolein. According to the invention a composition which releases acrolein upon contact with water at the site of use and is easy to handle is used. The composition in accordance with the invention contains an acrolein acetal, preferably 2-vinyl-1,3-dioxolane, and a compound hydrolyzable to an acid with a pK.sub.s value of less than 4, especially one from the series of organic acid anhydrides, organic acid halides and inorganic halogen compounds forming hydrogen halide upon hydrolysis.

Method and composition for combatting microbial, vegetable and animal

Stretches of flowing water are doped with acrolein for the purpose of preventing excessive growth of plants and algae. In order to avoid transport of acrolein, acrolein is produced at the site where it is required by deacetalation of an acrolein acetal in the presence of an aqueous mineral acid. No electrical energy is necessary for this process. An acrolein acetal and an aqueous mineral acid solution are delivered from compression-proof storage tanks into a mixing chamber by the application of pressure from a pressure cylinder. The mixture is passed through a deacetalation reactor unit which includes a tubular reactor part and a container-shaped reactor part.

Method for treating water with acrolein and a device for the performance

Liquid acrolein, whose hazardous properties make handling difficult, is used to dose aqueous systems with acrolein in a biocidally effective concentration. Disclosed are agents which increase the ease and safety of acrolein handling and which are characterized by a content of 30 to 95% by weight acrolein and 5 to 70% by weight inorganic carrier materials. Silicas are the preferred carrier materials. The powdery or highly viscous mixture of substances will preferably exist in molded form and is additionally provided with a cladding that is impermeable to acrolein vapor. In dosing the aqueous systems, the agents are introduced directly in the water whereupon the acrolein is released.

Agent for dosing aqueous systems with acrolein, processes for making

Calcium formate is produced in aqueous phase by reaction of calcium hydroxide with formaldehyde in the presence of hydrogen peroxide or by reaction of calcium peroxide with formaldehyde. The molar ratio of CaO or Ca(OH).sub.2 to H.sub.2 CO to H.sub.2 O.sub.2 is 1 to 2 to 1-1.2 and the molar ratio of CaO.sub.2 to H.sub.2 CO is 1 to 2. Calcium formate is obtained in an almost substantially quantitative yield and in highly pure form. The process avoids the disadvantages of prior processes for the production of calcium formate from calcium hydroxide and formaldehyde.

Process for the production of calcium formate

Aqueous solutions can be doped in a simple, safe and economic manner with acrolein in biocidally effective concentration by converting acrolein acetals in aqueous phase in the presence of a strongly acidic deacetalation catalyst into acrolein, cleaving the alcohol component, constantly removing the formed acrolein from the decetalation mixture and transferring it by means of an inert gas stream or a liquid jet pump with the aqueous solution to be doped as jet fluid into the aqueous solution to be doped.

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Gelnhausen-Hoechst, Germany

Martin Trageser